There should be some mechanism to verify minimal PHP config requirements before software installation, i.e.:
list of required extentions
I have found some software (i.e. joomla 1.6) installed properly, but not run on installed site, (blank page) due to missing curl extension.
Not all PHP configurations are the same (and overbloated :-) )
error_log of course indicates the problem, but softaculous is for lazy and non-technic users after all ;-).
Such user-friendly error at verification stage could suggest to modify the config to meet minimal requirements first.
PHP configuration verification before installation