6435
I've installed on XOOPS 2.3 RC2, and it gives me the same error as you, i.e. there is a conflict with the XoopsFormEditor being redeclared. I commented it out (file formeditor.php, lines 50-76), and then I got error with XoopsFormSelectEditor being redeclared. I commented it out as well (file formselecteditor.php, lines 46-70), and now I was able to add a new page.
However, for the new page, the Extended DHTML buttons are not there (they are visible in the Referrer and Links pages). It's just a plain text window, but the XOOPS codes, e.g. [ b ]bold[ /b ] are working.
Also, once you add the first custom page, the permissions are working.
I guess, we'll have to take a closer look into making it work with 2.3.
But try to make those changes and let us know if it also works on your XOOPS.