Unable to upgrade Full Frame Pro from 2.3 to 4.0.1

The admin section of my site is not allowing me to complete certain functions, such as customizing the Full Frame Pro theme. In fact, all theme customization options such as customize, widgets, menus, etc. are unavailable. I thought upgrading from v 2.3 to v 5.0.1 would be a possible solution. However:

1. I don't have FTP access at present
2. The Catch Updated plugin (v. 1.6.2) is not allowing me to upload the v 5.0.1 Full Frame Pro theme from my desktop. the "Upload Theme" is unresponsive.

Any suggestions/help on accomplishing the update? Thanks, JG