[Plugin: SimpleModal Login] slight CSS problem

Hi Eric

I’m having a slight css problem with the plugin and its popup form, using twentyeleven or possibly even twentyten and any dependant child themes the popup form is appearing partially obscured by the branding banner graphic

I think I need to apply a z-index value to get the form to appear in a layer above the branding graphic, but am unsure which of the many references in the default.css to apply it to – is the osx.css still needed or is it now redundant? when looking with web inspector it does not appear to be linked to.

I’m also using smcf which does not have this issue and I have noticed won’t popup when the other is active and vice versa.
the site I’m having this problem on is aireriverstrust.org and its multisites.

http://wordpress.org/extend/plugins/simplemodal-login/