Creating a new project with custom fields using web services

Question

I've been trying unsuccessfully for the last week or so to successfully create a new project from web services and I believe the main problem that I've been running into is that one of the required fields is a custom field. I've tried creating the Project
in a couple of different ways and haven't had any success up to this point, so any help would be appreciated. I've tried creating it with both a REST call to /_api/ProjectServer/Projects and a SOAP call to /_vti_bin/PSI/Project.asmx. Below are the best shots
I've made at the two different calls with the errors I received. If anyone has any leads on the best way to do this the help would be appreciated!
REST POST /_api/ProjectServer/Projects
'odata.type' : 'PS.PublishedProject',
'Name' : 'OData Name',
'Custom_9d77d62aa92e4d40adc8446c90eb7456' : "O&M"
Response
error: {
code: "11713, Microsoft.ProjectServer.PJClientCallableException"
message: {
lang: "en-US"
value: "PJClientCallableException: CustomFieldRequiredValueNotProvided CustomFieldRequiredValueNotProvided mdpropuid = 9d77d62a-a92e-4d40-adc8-446c90eb7456"
SOAP POST /_vti_bin/PSI/Project.asmx
<?xml version="1.0" encoding="UTF-8"?>
<soapenv:Envelope xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/" xmlns:proj="http://schemas.microsoft.com/office/project/server/webservices/Project/" xmlns:projds="http://schemas.microsoft.com/office/project/server/webservices/ProjectDataSet/">
<soapenv:Header />
<soapenv:Body>
<proj:QueueCreateProject>
<proj:dataset>
<ProjectDataSet xmlns="http://schemas.microsoft.com/office/project/server/webservices/ProjectDataSet/">
<Project>
<PROJ_UID>e1c2d38b-1529-4128-b707-42a94045e55b</PROJ_UID>
<PROJ_NAME>Proj Dept Test 2</PROJ_NAME>
<PROJ_TYPE>0</PROJ_TYPE>
</Project>
<ProjectCustomFields>
<CUSTOM_FIELD_UID>4802a711-62a0-4f84-8e08-c7d22daadb5b</CUSTOM_FIELD_UID>
<PROJ_UID>e1c2d38b-1529-4128-b707-42a94045e55b</PROJ_UID>
<MD_PROP_UID>9d77d62a-a92e-4d40-adc8-446c90eb7456</MD_PROP_UID>
<FIELD_TYPE_ENUM>21</FIELD_TYPE_ENUM>
<CODE_VALUE>a47930d6-b89d-4f3a-b4e3-522015fe82a1</CODE_VALUE>
</ProjectCustomFields>
</ProjectDataSet>
</proj:dataset>
<proj:validateOnly>true</proj:validateOnly>
</proj:QueueCreateProject>
</soapenv:Body>
</soapenv:Envelope>
Response
<s:Envelope xmlns:s="http://schemas.xmlsoap.org/soap/envelope/">
<s:Body>
<s:Fault>
<faultcode>s:Server</faultcode>
<faultstring xml:lang="en-US">ProjectServerError(s) LastError=GeneralUnhandledException Instructions: Pass this into PSClientError constructor to access all error information</faultstring>
<detail>
<errinfo>
<general>
<class name="General Unhandled Exception in _Project.QueueCreateProject_">
<error id="42" name="GeneralUnhandledException" uid="184feeaf-906a-e411-9b2a-00155d388b02" Exception="System.Data.StrongTypingException: The value for column 'PROJ_TYPE' in table 'Project' is DBNull. ---> System.InvalidCastException: Specified cast is not valid.
at Microsoft.Office.Project.Server.Schema.ProjectDataSet.ProjectRow.get_PROJ_TYPE()
--- End of inner exception stack trace ---
at Microsoft.Office.Project.Server.Schema.ProjectDataSet.ProjectRow.get_PROJ_TYPE()
at Microsoft.Office.Project.Server.BusinessLayer.Project.FixupProjectType(ProjectDataSet projDS)
at Microsoft.Office.Project.Server.BusinessLayer.Project.QueueCreateProject(Guid jobUid, ProjectDataSet dataset, Boolean validateOnly)
at Microsoft.Office.Project.Server.Wcf.Implementation.ProjectImpl.&lt;>c__DisplayClasse.&lt;QueueCreateProject>b__d()
at Microsoft.Office.Project.Server.Wcf.Implementation.WcfMethodInvocation.InvokeBusinessObjectMethod(String businessObjectName, String methodName, IEnumerable`1 actions)"/>
</class>
</general>
</errinfo>
</detail>
</s:Fault>
</s:Body>
</s:Envelope>

Answer 1

Julie,
You can create the fields that are project specifc & you can create fields that apply to all projects but have specific options for projects. Your goal is to create fields that are specific to each project, but right now you get all fields from you old project - is this correct?
From your description below it appears that the fields in your original project are marked as applied to all projects & hence when you create a new project they are inherited. If you mark those fields as applied to certain project & then create a new project those fields will not be inherited.
But you are right in the sense that it is limiting that there is no multi-select for "applies to" field.