Homepage corrupt after update to 12.5

Hi,
I updated my site yesterday to 12.5. This resulted in tagDiv displaying code instead of the correct formatting. I have tried to revert to 12.4 but the issues remains.
Homepage displays: [td_block_big_grid_1 meta_info_vert=”content-vert-bottom” image_zoom=”yes” show_author2=”none” show_date2=”none” modules_category=”above” overlay_general=”eyJ0eXBlIjoiZ3JhZGllbnQiLCJjb2xvcjEiOiJyZ2JhKDAsMCwwLDApIiwiY29sb3IyIjoicmdiYSg…

I am unable to manually recreate the page as it will not add new elements – spinning busy icon instead and can’t save the page.

Is there a fix?

After attempting to fix this issue my instance of tagDiv now appears to be corrupt. TD Composer is behaving strangely.
I can no longer attempt to update the Theme to the new 12.5.1 as it requests FTP access. My site’s FTP is locked to specific FTP and is not accessible from external locations.
The td_composer folder now insists on being ‘_td_composer’ and is impossible to change back to ‘td_composer’.
Please assist me in resolving these issues.