I took the decision to stick with J1.5. Period. So expose came into question as a com working in this env. Well, I installed the J1.5b2, offered to public at the beginning of May and put over the latest night builds. The install went wrong at first with a) sorry, legacy mode OFF. All right, I set legacy mode ON. b) second try produced error message .. "Do you want to install that com second time?" Why that? I checked the component dirs by simple ftp and there wasn´t anything like com_expose. So to make it short, after diiferent experiments I´ve got out how to get it working ... a) install virgin J1.5b2, b) install expose, c) finally install the latest night build. I had to install night builds because of problems I had with another modules.
There´s also another quite annoying trouble with the com. I couldn´t find a way how to declare to transfer multile files from the bucket - a certain selection - at once, not just a single file which is currently offered.
Nevertheless I use the com and am looking forward when bugs disappear:-)