Hiya,
Sorry if this is a bit late.
Question, there isn't a WebFocus 6? There is Focus Six.
I've migrated Focus Six => WebFocus 5 and then to WebFocus 7. The jump between Focus & WebFocus wasn't that big what comes to code in batch runs, but you need to rewrite all the forms for the UI. You can copypaste most of it but not really transfer 1:1.
Now then comes the fun part. The old six & WF "engine" lets stuff slip through. So if you had guys coding stuff bad, it "worked" fine. However the "engine" is much tighter version by version even say 5.1 and 5.3 and gets tighter in the newer versions. For example IF-THEN-ELSE has to have an ELSE in 7, when in 5 it reverts back. Like using & and && constants. In 5 you can 'rewrite' it if something is true, else it stays the original value, in 7 touching the constant nulls it.
Small stuff like this, so basically I do a "parallell universe" and see what happens, if the result with old and new 1:1 it usually doesn't have any problems after you find the few snags.