Now after reinstalling the system (for another reason) everything worked fine with b43 !!!
Now everything is fine.
The broadcom-sta package is not being deleted because it was deleted earlier.
I have made up my instructions for the future.
I consider the question closed, thank you for your help.

After reboot, Wi-Fi is gone...
wlan0 is missing after ifconfig -a

The message in the BIOS:
ERROR: wl_cfg80211_detach
is missing.
Probably the changes should be included in the startup?

Good afternoon, Dimitris!
Only the "other solution" with b43 helped !!!
Now, after reinstalling the system (for another reason), everything worked fine.
Thank YOU so much for your help !!!

Thanks for the quick response.
I'll reinstall the system tomorrow and try.

Good day, Dimitris! I installed your Slackel64 7.5 "Live Openbox" on an old laptop with Broadcom BCM 4311 (rev.01). I really liked the build. Problems: 1. When booting into the BIOS (in both modes) a message pops up: ERROR: wl_cfg80211_detach Wi-Fi is not visible, wired Internet is normal ...