[WD21] HFSql + Native access = showstopper?

Hi ALL

I was doing some totally innocent improvements in my ERP's salary system, When I started to have problems when testing it: under certain condition A certain button code was not executed, under some other condition it was.

OK, I thought, no big deal, WD has just lost its marbles again, so it's time to clear WD's thoughts by deleting the .CPL directory. So I saved and closed the app, and deleted the app's .cpl directory.

Then I re-opened the app, and voilà, A brand new compilation error appeared that I have never seen before:

"The project is using native accesses, which is not available in integrated framework.
Appname, , line 1, column 1"

Obviously I am using native access, because the data is in HFSql (Classic) data files,
but it's rather weird error message, considering that this happens in testmode...

Recompiling does NOT help.
Running the app repair process does NOT help.
Restarting Windows (7) does NOT help.

Anybody seen this? What could it mean? How can I get rid of this nasty showstopper?

Best regards
Ola