> Then I extracted D4_DCU to get the stuff I don't have the source

for -

> IB_CONSTANTS.DCU etc.
> I opened IBO_C4.bpk and compiled it.

Have you EVER managed to compile the partial source version with BCB?

As far as I knew it was not possible. There are no .hpp or .obj files
distributed (or did not use to be) and so BCB will insist on trying to
compile everything - and fail.

If you ask Jason nicely (privately) he may allow you access to full
source under the trustware licence.

Geoff Worboys
Telesis Computing