As I said, the small appearance window disappears too quick to see anything, but it seems to look like a yellow/green message at the right bottom of the display.

Something must be wrong but how to find what ?
Must add I recently updated BIAB 2019 from its last previous version (don't remember the build # 632 ?? not sure) to 644. BIAB 644 worked OK.

Then I set up BB2go on an iPad which worked OK after performing the necessary network and firewall tweakig.

In addition I had to reset my install in C:// to be in in folder bb instead of BIAB. in 2019 I renamed bb to BIAB and I just did the reverse renaming BIAB to bb. because apparently BB2go expects that ..