This is a short list of things, that are different between the compilers being used with VS Smalltalk 3.0 and Visual Smalltalk Enterprise 3.1.
no COM support
block classes: Context/HomeContext
negative numbers: minus sign and first digit must not be separated by white space
literal arrays: literal arrays only contain Strings, Characters, Integers, Floats and Symbols
block class: BlockClosure
negative numbers: white space allowed between minus and first digit
literal arrays: literal arrays contain Strings, Characters, Integers, Floats, nil, true, false and Symbols