2
Check the group permissions of your module: Is your users group allowed to access, view or administer the module?
Set debug on in the system preferences and see if there are any messages.
Check also all install and other text files to see if all things are correctly installed and provided or setup (eg libraries, module dependencies, folders setup and permissions, ...)
I can't tell you about differences of the two modules.
But if you look in the SQL files you can identify the tables used in the modules and identify the datafields.
For each field you must learn what the purpose or function is: the name will tell already a lot.
The two modules will have some fields with maybe a different name but with a similar use. Once you have these related fields you can copy them from one table to the other with phpMyAdmin. Eg.:
INSERT INTO desttable (field1, field2, field3)
SELECT fielda, fieldb, fieldc FROM srctable;
Install on your local PC eg XAMPP with XOOPS and your modules as on the website. With a copy of your database, you have a complete play garten to experiment.
Some examples of conversion between two forum modules are
here.