The reality is that people are fickle and do not like change. I stopped developing themes when phpbb3 came out because I didnt actually like it and I know from a lot of feedback many people felt the same way. Personally I think the admin area is far too complicated - pages and pages and pages of opt...
I have a template and it works fine except for one thing. On the viewtopic page there is a 1 <br> gap between the "new topic" and "post reply" buttons and the table below it (the top row containing View previous topic :: View next topic) Now the problem. If the post gets 1 reply ...
it would be good for you to contact the author and ask first, before actually doing it.
As for what to actually write, it is best to not actually change anything, just add your own info to it.
the general rule is that it should look quite different to the original - not just a few font colours changed etc.
I tell people that they should use "powered by php blah blah...xxx theme by yourname based on yyyyy theme by zzzzzzz". If that makes sense?
I just had a quick look at the source code and it appears that someone has added the colour to tables in viewtopic_body <td width="150" align="left" valign="top" class="row1"><TABLE ALIGN="CENTER" BGCOLOR="#BFBFBF" CELLPADDING="1"...
you should look in the language files (language/lang_english/lang_main.php) and not the template files, however i think if you change the text it will change it everywhere total posts: is used, and not just on that page.