Our site coded in Smarty is doing fine when we were created new skins ending with filenames of filename_New.php and filename_New.tpl , (sometimes _Newskin.tpl even) . When we found the look of the skins we like, we rename the pages away from _New to just the filename without the extension that recognises it is the new skin. We also did word replacement of the codes in the files to point to filenames without the extension of _Newskin or _New , but nevertheless there are some errors. We have reinstated an original version of the site on another host's domain, allowing a one-to-one comparison with the new one where we rename away the extensions, hoping a skilled programmer can detect all the bugs and fix them up in time.
There are 5 site templates for the corresponding new skin to each file, but the pattern is the same for all.
We used a software to do replacement of the filename extensions in all the files' coding to point to the shortened filenames, neverthless, there are bugs that need to be fixed when we view the site pages.
We pretty much have done over 95 per cent of the renaming, but there are some bugs left to be fixed.