I'll upload a new version of this mod with some clearer instructions this weekend.
Regarding the google/yahoo bot:
"/ubbthreads/showthreaded.php?Number=108450&page=vc"
is an url with invalid parameters.
It should be
"/ubbthreads/showthreaded.php?Number=108450&page=&vc"
Note the additional &.
So the securiy alert is correct. This will not be changed, as this is the desired behaviour. The page parameter should be an integer value.
In your case, it has the value "vc" which is not allowed.
Apart from that, you can change the behaviour by modifing the known_params array in Validate.php.
Search for "page => 'int' and replace it with "page => 'alphanum'.
But beware, that this may lead into a security problems.
Regarding the unknown parameter
"UNKNOWN PARAMETER FOUND: sub. Value was: browser_misc"
The script /ubbthreads/feeds/rss.php isn't a standard ubbthreads script, is it?
You can manually add new params to the validation script. Have a look at the readme.txt for further instructions on how to do this.