Since the game's forum barely has a few threads and doesn't seem to be visited, let me ask you here:

How many levels are there? In the previous Zachtronics programming games, you had at least a rough indication how far you were in the game, but not here.

Also, does anyonw know if there are any planned additional levels/campaigns, like for Infinifactory and TIS?

Thanks.

Cool, thanks.

This game is fun! Better than TIS.

So far SpaceChem then Shenzhen then Infinifactory then TIS-100, but all were extremely fun. Haven't tried Opus Magnum yet.

I'm bad at all these games sadly and as such haven't finished any. Really enjoyable though. TIS-100 is great but required a lot more effort to get into. My favourite is Infinifactory and the card game in Shenzen. ;)
I really should buy Opus Magnum sometime.

The only annoying thing in Shenzhen now is some puzzle having problems plcing all the wires. I wish the wire grid was smaller.

Ugh, the wiring gets ugly at times. Gives spaghetti code a new meaning.

Sorry to bump this, but just a quick question.

I'm on what appears to be the last level now (The Big One), however this post
http://www.zachtronics.com/firmware-update-3/
Suggests there are 10 more puzzles. Are these 10 included on GOG? Are they part of the 30 levels, or are they extra ones that will get unlocked after I finish the last one?

The ConceptMAIL transcripts show... 5 assignements after The Big One. While this one
https://www.reddit.com/r/shenzhenIO/comments/5pev64/bonus_campaign_top_list/
Shows 10 levels that have different names.

Could someone expalain please?

After the Big One, a new "area" will open up with 10 more. LOGIC BOARD is the last.

Sorry, I have no clue. I don't see anything in the link you provided stating when 1.3 came out; maybe it came out before the game was released on gog. I bought it on the day it was released, and noticed no significant changes as I went through the game. I looked at it just before answering your question, and it still looks the same. A quick count shows me 43 uniquely named .puzzle solutions in my save dir, not 30, so interpret that as you like.

edit: as I mentioned in this empty thread, there was some text at the end of the game that implied there might be more. At the time, I verified that there were no new puzzles, apparently by looking in <game dir>Content/descriptions. That last message seems to have changed since then, but I am still pretty sure I solved all the included puzzles.

1.3 cameout Nov 11 2016.

Anyway since all previous Zachtronics games had all levels included on GOG I assume this does too. Just don't want to miss any content.

In case anyone else is wondering: Yes the 10 extra levels after the Big One are the ones added by the update.