Migration Assistant transfer hangs up

Question

In the week since I received my new iMac with Snow Leopard 10.6.7, I have been reading archived threads here about my options to transfer data (including applications) from my old G4 running Panther 10.3.9. Although I read mixed opinions about it, I decided to try Migration Assistant (MA). The iMac got set up perfectly, all of its original software got updated, and I installed Rosetta in order to recognize and run PowerPC applications migrated from the G4. I checked the G4 with Disk Utility (from its original install CD) and it reported no problems. I repaired permissions as well.
Both computers were on an Ethernet LAN, but when I proceeded with MA and chose wired network, it told me to start MA on the old computer. As the G4 did not have MA (introduced in Tiger 10.4), I could not use this method. (I saw that problem here in an archived thread, so I foresaw it as possible for me too.) So I used a FireWire connection via Target Disk Mode (TDM). Rebooting the G4 into TDM worked fine, and MA saw it. I chose most of my main G4 User account to migrate, deselecting a few insignificant items (such as time zone) but transferring Applications and essentially all other files. MS counted about 45 GB.
The migration appeared to start OK, estimating it would take 11-12 hours. Since it started last inght, I let it run overnight. After about 11 hours, it was approx. 40% complete (by progress bar) but said it had 10 h 15 min to go. After about 13 hours total, it said it had 11 h 17 min to go, with no significant change in the progress bar. I checked the Console, and it had 4000 messages (which may be a limit, as older ones disappeared after a few minutes to stay at 4000-4001) reporting every few seconds an error related to com.apple.storeagent. Those had started at least by 4:50 AM. They included the phrase "Job appears to have crashed: Trace/BP trap" and a phrase related to trying to restart. (Unfortunately, I had to leave for work and cannot report more details at the moment, though I can later.) All messages appeared to relate to com.apple.storeagent.
Is MA really hung up, or could it be stuck on one file or category of files that takes much longer than others? The Console messages did not look good to me. Is there anything I can do on the iMac, particularly related to storeagent, than I can do to resume migrating? If I cannot, can I just quit MA (there is no Cancel button) and about 40% will be migrated successfully? If I can fix the storeagent problem, could I probably restart MA? I think I cannot do one User's migration in parts, can I? (Meaning perhaps to choose Applications and certain settings first and then run it again for other files?) I think not, because the old User will have been migrated on the first run, and MA will not repeat it with that User exisiting on the new iMac. I could, however, rename my User on the second run to get the other files. Is there any advantage to that if MA hung up on a particular item in some category?
Thanks in advance for any advice. I am not in a big hurry, as I have another iBook and a Windows PC, but I would like the migration of my G4 files to be achieved as successfully as possible.

Answer 1

I have been gradually transferring content from the old G4 PowerMac to the migrated User account on the new i7 iMac. That has mostly been done via Ethernet LAN (which is fast enough and much faster than attempts to migrate via FireWire). I discretely copied over certain Library folders that were not already in place on the iMac. I have run installers again whenever they were available. The new account seems to be working fine. (There is a deficiency with AOL Desktop for Mac being unable to read individual files that are in AOL Mail format, as saved by the predecessor AOL for Mac OS X, of which I have thousands saved over the last 21 years, but I am dealing with AOL to try to resolve that.)
However, I have continued to have problems with a FireWire connection between the two computers, which I have resumed diagnosing this weekend after receiving a new FireWire cable. I tried to make a Disc Image of the G4 using its own Disk Utility (10.4.4) to save to an external USB HD, but it always gave the error "Device busy." When I mounted it on the iMac via Target Disk Mode, Disk Utility on the iMac was never able to finish making a Disc Image, terminating with an error after several hours of trying. Verifying the G4 via TDM using the iMac's Disk Utility said that it had problems (after the G4's own Disk Utility repeatedly said it did not), and then attempting to Repair those problems led to its saying the G4 drive could not be repaired. I booted the G4 into its original installer disc and ran Disk Utility to repair any problems the iMac's connection may have caused, and it was fine.
Problems have been occurring using either of the two FireWire ports on the G4, any of three different 400/400 FireWire cables with a new 400/800 adapter as well as with a new 400/800 cable. An external LaCie "Super Writemaster" CD/DVD drive was able to write a music CD connected to the iMac via FireWire, but it was repeatedly unable to write 4.25 GB of files to a DVD-R disc. The errors were to the effect of "a file was modified while being copied." Through a USB connection to the iMac, the LaCie copied the same files to a DVD fine. The LaCie then copied 4.33 GB from the G4 via FireWire just fine.
I am coming to suspect that the problem is the FireWire connection (port or controller?) on the new iMac. Is it possible for a FireWire connection to "mostly work" (enough to copy hundreds of MB of files but not GB) but fail during larger transfers? Every disk I have connected has mounted (so the symptom is different from that of other people who have posted problems related to iMacs' FireWire, who could not mount disks), but large transfers have always failed. I have also reset the System Management Controller.
I know this has digressed into a different topic from Migration Assistant hanging up, but your guess along the way might be correct as to the physical problem: "There's clearly something wrong with the old Mac, a Firewire port, or cable, or something"...except that it may be on the new iMac. Should I post a new question about this problem? I would like to diagnose the iMac's FireWire port. Apple's Hardware Test claims there are no problems, but I do not know if it could detect one like this. I have made an appointment at an Apple store next Saturday (while the iMac is still under warranty), but the nearest one is over two hours away and I am dubious that they will be able to determine a specific cause. I may end up keeping a new iMac without a reliable FireWire port. It is problems like this that make me dread buying new computers. I have had this iMac almost a month and cannot give up my G4 yet in case the iMac needs repair that takes it away for two weeks between visits.