Andrew Tween wrote:
>> Thanks for finding this. I'm still at a loss why this happens (perhaps
>> Monticello gets something wrong in its initialization?) but I have added
>> those two lines to the SqueakMap installer script. This should prevent
>> crashes like you were seeing.
> 
> In case I didn't make it clear in my original post, you will probably also need
> to include the modified ExternalType class>>#initializeStructureTypes method.
> The two lines, on their own, didn't fix it.

Actually, it turned out that this fix was not entirely correct, but it 
pointed to the problem. It seems as if the initialization of external 
structures is indeed broken but in a subtly different way - and that 
calling #compileFields on all the external structures does the right 
thing once the load is complete. I have updated the installer in the 
mean time to include that fix, if you could give it a try and let me 
know if you find any other issues with it I'd appreciate it.

Cheers,
   - Andreas