Studio Problems in 4.5.1 - from no edit through blank screen

[jmugauri]

I am running a new install of Sugar Open Source on Fedora Linux with Apache2 and MySQL 5.1.

My original problem was Studio would not let me modify any layouts OR view custom fields I'd only just installed.. After (perhaps wrongly) following the instructions in the Enabling a custom module for Studio Wiki, i repaired Studio from the Admin 'repair' menu.

Now, when i click on Studio from the admin menu (as the admin who ran the repair), just a blank page comes up!! I'd like to:
1. Fix Studio so that even the meagre choices i had are available again for the admin profile that ran the repair
2. edit my layouts et al without hassle (MOST important!), instead of getting an empty page headed 'Studio' when i select edit layout.

Also noticed that, even thought in an earlier dialogue I specified the modules I'm adding custom fields to, the values entered in the database (table: field_meta_data) don't make sense..
1. id is automaticaly prefixed 'Studio'
2. custom_module is set to 'Studio' instead of the one i selected with the wizard

[jmugauri]

Downgraded to PHP4 and installed PHP4-JSON 1.1 (and all other requied packages) and it works fine, in case anyone has the same problem