Various: program problems

[Geist-zz]

Boekhoudprogramma - not a valid BC program (partial modification/Google translation, still has few STRING$ left)
Weer - not a valid BC program (partial[?] modification/Google translation)
Solitair-Dame - no REM in line 30000 (or maybe interpreter should ignore it?)
Tennis - runs too fast (maybe there should be a slowdown option in the interpreter?)

Tested under Firefox (BTW, Edge tends to slow down execution of programs for a while).