I was using an "old" version of KeyValueStore. Having found this problem:
https://www.b4x.com/android/forum/posts/557508/
I replaced the old class with the latest one (and replaced all PutSimple and GetSimple with Put and Get).
Running the project, I get:
java.lang.NumberFormatException: Invalid double: "null"
executing the assignment LastVersion = Version(0) (as you can see LastVersion is a string variable so this does not make sense [also Version is an array of strings]).
KeyValueStore is not involved in any part of this phase (GetOnlineVersion is a resumable sub which downloads a simple string from Internet, splits it and returns Version(), correctly).
How could this have happened?
Thank you