@t0nai That's actually good news; the unknown error we understand and can usually fix (not always, but usually). Is there anything different about that new user account, like is one of them admin and the other not, or are the settings different? This is for my curiosity and future troubleshooting; feel free to leave the question alone.
In your case, with only the base game installed, you'll need to edit two .sgr files in TS3's program files to force the game to recognize your graphics card. Some iMacs come with dedicated graphics cards, and others don't. The specs you listed refer to an integrated card, but if you have both, the dedicated card might not have been listed in the initial specs. So please go to About This Mac again, then click System Report, then Graphics/Displays, and let me know which card(s) you see listed. Once I know which card you have, I can send you instructions for the edits, or a link to instructions if Bluebellflora has already prepared the text for your card.
Also, undo the edit you made to bypass the launcher. That can come later, if you want.
I only have the integrated Intel Iris pro 1536 MB card.
This is what my report says (unfortunately in German, but I guess the most important stuff is understandable):
Chipsatz-Modell: Intel Iris Pro
Typ: GPU
Bus: Integriert
VRAM (dynamisch, maximal): 1536 MB
Hersteller: Intel
Geräte-ID: 0x0d22
Versions-ID: 0x0008
Metal: Unterstützt, Funktionsset macOS GPUFamily1 v4
Displays:
iMac:
Displaytyp: LCD
Auflösung: 1920 x 1080 (1080p FHD - Full High Definition)
UI sieht aus wie: 1920 x 1080
Framepuffertiefe: 24-Bit Farbe (ARGB8888)
Hauptdisplay: Ja
Synchronisierung: Aus
Eingeschaltet: Ja
Rotation: Unterstützt
Helligkeit automatisch anpassen: Nein
Verbindungstyp: DisplayPort
Last time I checked Bluebellflora only had instructions for the late 2013 21“ iMac (iMac 14,1) with the Intel Iris Pro 5200
@t0nai You're right, the German isn't an issue; all the important information is easy to find regardless.
You do in fact have an Intel 5200, even if it's not listed that way. I checked Bluebellflora's files, just to be sure, and the device ID she lists matches yours, so it should work fine. You can download the text to add to your files here:
https://bluebellflora.com/2018/07/24/sims-3-mac-players-i-need-your-help/#Filesconfirmed
Be sure to test in the alternate user account, since that's the one that's being more cooperative, relatively speaking. An unknown error is better than no response at all.
I changed my .sgr files, but I still don't get the game to work. On the alternate user I get thte "Unknown error" message, and on my main user nothing happens.
@t0nai Can you post screenshots of the edits you did? Sometimes TextEdit messes with the formatting.
And I'd also like to see part of your deviceconfig, if you have one—just the entry between Graphics Device Info and Options, so from about 25 to 40 lines down.
