NAT migration on 8.2.4 to 9.1.2

Question

Hi,
I have new ASA 5545-X firewall with 9.1.2 software (default) and I want to replace old 5540 with current configuration on version 8.2.4
I copied the current asa 5540 config (old ver) to new asa 5545-x and start with the current configuration (copy flash:old_asa_conf running-config) and most of the commands have been migrated except the NAT configuration.
It is hard to manually change the NAT configuration as old asa config having more than 200 plus nat types configured.
Just want to know is this a normal behavior, why it didnt migrat the NAT configuration.?, do I have to manually configure the all NAT types configured in old asa ver. 
We can't even downgrade to 8.3 or 8.4 as new asa 5545-x supports 8.6.x and above. In that case will 8.6 code will automatically migrate the NAT config on old config with ver 8.2.4.?
Appreciate if someone can advise me this as it will be hard to configure all NAT configuration to new version. 
thanks..

Answer 1

Hi pkillurcco and Marvin,
Thanks for you for your time on this and interest. 
I was trying with http://www.tunnelsup.com/nat-converter and it helped me to some extend. however it can not convert the dynamic policy nat where you have match with ACL with destination port. 
Then I did convert the following NAT by manually, however when I tried with packet tracer it gave me xlate error. 
Here is the original policy nat.
access-list inside_nat_outbound extended permit tcp object-group LAN-SUBNETS host 89.211.xx.yy object-group http-https
global (outside) 1 interface
nat (inside) 1 access-list inside_nat_outbound
Here is the new nat once converted manualy,
nat (inside,outside) source dynamic LAN-SUBNETS interface destination static 89.211.xx.yy 89.211.xx.yy service obj_http obj_http
below is the packet tracer output which giving the xlate error.
xxx-xx-FW01# packet-tracer input inside tcp 10.130.100.1 80 89.211.xx.yy 80 detailed 
Phase: 1
Type: ROUTE-LOOKUP
Subtype: input
Result: ALLOW
Config:
Additional Information:
in   0.0.0.0         0.0.0.0         outside
Result:
input-interface: inside
input-status: up
input-line-status: up
output-interface: outside
output-status: up
output-line-status: up
Action: drop
Drop-reason: (nat-no-xlate-to-pat-pool) Connection to PAT address without pre-existing xlate
I would appreciate if you can advise me what exactly cause the above error. As per old ver config, when packet going from given source to the destination IP and the ports, it should do the PAT on outside interface. If I simply nat the source/destination IP to the interface it would allow to access rest of the ports as well.I have such many ACLs used for policy NAT with many interfaces in the old config and its working fine.
It would be better if I can find a tool to convert them as its going to be hectic for converting them manually and prone to be more error. If not I just need how to configure dynamic policy nat according to ACLs with destination ports as I given above.
thanks in advance.