I can't understand what you want.

If you want to change an externals, edit myalbum*_index.html in your template.

Do you know how to use template manager of XOOPS?

- copy template set from default to new name in template manager
- set default template set as the new template set in preferences
- edit myalbum_*.html in the new template set in template manager
(don't edit original template file)

Of course, some skills about HTML are needed.

If you mean changing the layout radically, you have to hack php files (index.php etc...)