Does the freeze happen when you click on the Somnasculpt Workshop menu option from the title screen, or does it happen when you click on the "Workshop" paper on the cork board inside the workshop level's office?

If it happens when trying to load the level, you might have a corrupt file. Try verifying the game files through Steam and see if that fixes it.

If it happens when trying to click on the cork board, do you have the Steam overlay disabled? The game uses the overlay to load the workshop page for subscribing to items. If it is indeed enabled, then it might not have loaded properly when you launched the game. Simply restarting should allow it to load.

If you can go into the level, does subscribing to items through the Steam client allow them to show up in-game fine? If so, a work-around could be to just subscribe/unsubscribe solely through the Steam client.

I deleted all workshop items and it does not seem to be happening any more.

Originally posted by Iras:

I deleted all workshop items and it does not seem to be happening any more.

Ahh, okay. If that was what fixed it, you might have been subscribed to a workshop item that was oversized and the freezing was related to the game trying to render it. If it happens again, check the file sizes of the items you're subscribed to and try unsubscribing from the ones that seem too large.