No, nothing changes in my case: DO-LOOPs nested in pairs must stay in place, because, generally, when some definite variables become TRUE in the second level, the DO-LOOP exites with EXIT DO, and the program goes to the DO-LOOP of first level, but here not necessary the program must loop the pair: here an other control of the variables determines if the program has to loop the pair, or exit and go to the second level of an other pair of DO-LOOP, and so on until the program ends or the user want to close it. _CONTINUE doesn't allow the described check of variables, but it is a useful command.