Now I get steam creash and an error message:
Failed to write file mymaps\metro_singleplayer_ct.bsp to Steam Cloud!
Please verify the filename and try again.

I've solved this by enabling Steam Cloud for Nuclear Dawn. But Steam started to syncronize about 300 MB with the cloud. And it also said that the limit is about 100 MB :)
I don't understand what's happening here.

I pressume that map files I publish are stored in Steam Cloud, then uploaded to workshop or something similar.

Againg having this problem. Steam cloud was disabled for some reason so I reenabled it. It synced 220 MB. But I still can't update Corner Intermediate map and get "Failed to update. Try again later" dialog.
Console says nothing

Due to a limit in the SteamWorks SDK functionality at the time that Workshop support was implemented in ND, I believe that there is a 100mb limit on the size of uploaded files.

This is no longer a limitation of that SDK, but will require an update to ND to take advantage of the expanded uploading capabilities. I will make a note to get that taken care of next time ND is worked on.

Note that there's also a 512mb limit per user for total ND Steam Cloud space (which is just configs and Workshop files). We can increase this if you are at or near it.

Additionally, you should be able to get more information by typing "workshop_debug 1" (without the quotes) into the game console before attempting the upload.

The file I'm trying to upload is 85 MB in size.
I've just retried with workshop_debug 1. Got this:

I think the problem is in Steam cloud size limit. You say it's 500 MB but I see 291MB in ND properties.
https://www.dropbox.com/s/n9ap99tskb86bfo/steam_nd_properties.JPG
So if I upload a 85 MB file I will exceed this limit

Originally posted by DIMEDROLL:

The file I'm trying to upload is 85 MB in size.
I've just retried with workshop_debug 1. Got this:

] sv_cheats 1 ] workshop_debug 1 [UGC] File (null)\136131359ll_thumb.jpg already in sync on client. (Duration: 43.715959 seconds) [UGC] File 136131359ll_thumb.jpg (884104004693678805) finished all operations! (Duration: 43.715990 seconds) Found tag: resource points

I think the problem is in Steam cloud size limit. You say it's 500 MB but I see 300 MB in ND properties.
https://www.dropbox.com/s/n9ap99tskb86bfo/steam_nd_properties.JPG

The screenshot shows 220.06 MB stored, leaving 291.94 MB currently available. That adds up to exactly 512 MB.

Unfortunately, it's still not quite clear why it's failing on the map file after syncing the preview image.

The problem is still not solved.
- I have 220 MB stored in Steam Cloud for Nuclear Dawn
- Steam fails to sync Nuclear Dawn with Steam cloud when I run the game
- Nuclear Dawn fails to publish an BSP file into workshop giving a 16 error code(timeout)
- Steam syncs my other games fine, but they have 30-50 KB stored in cloud

I assume that size matters here.

Originally posted by DIMEDROLL:

The problem is still not solved.
- I have 220 MB stored in Steam Cloud for Nuclear Dawn
- Steam fails to sync Nuclear Dawn with Steam cloud when I run the game
- Nuclear Dawn fails to publish an BSP file into workshop giving a 16 error code(timeout)
- Steam syncs my other games fine, but they have 30-50 KB stored in cloud

I assume that size matters here.

The timeout points to an issue with some of the Steam workshop servers in your region. It's possible that there are different servers that store generic cloud files versus ones that store published (workshop) cloud files.

I've been awaiting a response from Valve on this.

Opting into the new Steam Vclient Beta in steam's settings should now resolve this.

Still get the same error when trying to publish. Also, when I run ND from other computers Steam always can't sync with cloud at game start.

After the latest Steam update it finally worked. The map uploading was pretty fast. I didn't figure out what app did the actuall upload, Steam or Game.

I've tried 10 times in total to publish an update to a map today and always get this same error. However now it takes pretty long for error to be shown.

Did you get your problem fixed because im having the same problem

Originally posted by DIMEDROLL:

I've tried 10 times in total to publish an update to a map today and always get this same error. However now it takes pretty long for error to be shown.

No. May be if you make 30 tries to publish it will work.
You can post a download link to your map in general discussions:
https://steamhost.cn/steamcommunity_com/app/17710/discussions/
server administrators will pick it up and host on their servers if they like it