This is not a big deal, but I build my projects with Microsoft's VC++ compiler, and I set the warning level to 4. When I build AngelScript targeting the x64 platform I get the following compiler warning.

>source\as_builder.cpp(240): warning C4267: 'initializing' : conversion from 'size_t' to 'AngelScript::asUINT', possible loss of data

I would recommend an explicit cast here so that the warning does not appear.

asUINT numTempl = (asUINT)engine->templateInstanceTypes.GetLength();