Userforms Not Saving and Disappearing

Hi All - apologies for the length.

Project 2010 (14.0.6023.1000) Standard SP1 MSO (14.0.6129.5000), running in Windows XP Professional SP3.

I have been having problems with UserForms in my global file - occassionally disappearing or becoming otherwise inaccessible ("File not found" errors and "Automation Errors"). I initially thought I had some sort of corruption in the global file itself, so exported everything and rebult the file from scratch multiple times, but the errors kept appearing intermittently.

While most of the behaviour is intermittent, and therefore can't be reliably reproduced, I've isolated some reproduction steps which cause issues to recur - and this happens on a blank global file, with nothing in it.

So far I've tried:

• Deleting the global file, forcing MSP to create a blank one
• Deleting all Ribbon/Quick Access customisations (wasn't hopeful on that one, but wanted to rule it out)
• Repairing my installation of MS Project and restarting the workstation

But all to no avail.

The following steps are reproduce the issue 100% on my workstation - I'd be grateful if anyone else could also reproduce:

Issue A - User Form Changes not Persisting

1. Delete the existing global file from [Profile]\Application Data\Microsoft\MS Project\14\1033\Global.MPT
2. Open MS Project
3. Open the VB Editor (View > Macros > Visual Basic)
4. Right click on ProjectGlobal (Global.MPT) and select Insert > Userform
5. Close the userform that just appeared (UserForm1)
6. Reopen the userform and make a change (i.e. change the caption to "UserForm1234")
7. Click the Save button on the VBE toolbar
8. Close and reopen the userform
   
   RESULT: The change made in step 6 does not persist. It has reverted back to its original state.

Issue B - '' could not be loaded
Continuing on from the scenario above:

1. Right click on ProjectGlobal (Global.MPT) and select Insert > Userform
2. Close the userform that just appeared (UserForm2), and the form behind (UserForm1)
3. Reopen the userform (UserForm2)
4. Change the form name, e.g. from "UserForm2" to "UserForm2345"
5. Click the Save button on the toolbar
6. Close and reopen the userform
   
   RESULT: Error message displayed - '' could not be be loaded.
   The form now can't be opened or exported

Issue C - File not found
Continuing on from the scenario above:

1. Right click on ProjectGlobal (Global.MPT) and select Insert > Userform
2. Click the Save button on the VBE toolbar
3. Close the userform that just appeared
4. Reopen the userform (UserForm2)
5. Shorten the form caption from "UserForm2" to "UserForm2468"
6. Click the Save button on the toolbar
7. Close and reopen the UserForm2
   
   RESULT: Error message displayed - File not Found

Issue D - Application Crash without Error, Corrupting Global
Continuing on from the scenario above:

1. Open UserForm2345
2. Open UserForm2
   
   RESULT: The MSP and VBE applications close immediately without giving an error
   
3. Reopen MS Project
4. Reopen the Visual Basic Editor
   
   RESULT: Error message stating Errors occurred during load.
   
   
   The ProjectGlobal is now named with the full path to the Global, and contains none of the forms created in the previous steps: