I could locate at least the register problem. The reason was an outdated manifest xml I added to jOpenSimRegister-System by mistake.
Please download the new versions (0.2.1.2).
After installing, go to "Extensions" --> "Plug-in Manager". Click on "System - jOpenSimRegister" and have a look on the right side: "Enable Register Forms". Ensure that the desired form is enabled.
Click on "SAVE" even if the forms where enabled before. Like this, the parameters get saved correct.
Sorry for this inconvenience
Greetz
FoTo50