I have been using Fomapan now for a number of years without problems, developing in both Rodinal 1/50 and D76, the only time I have had problems is when using a acid stop bath, plain water stop seems to suit this film, I use 3 changes of water, invert 15 times with each change, then fixer, if you do use stop then only 10 seconds max, with Rodinal develop anywhere between 11 and 17 minutes depending on the subject, if it is a high contrast then 11 minutes if low contrast then 17, agitate for the first minute, then two inversions every 30 seconds, which give negatives with lovely tonality,
Richard