Hello,
I've used MikroTik for quite some time now, never tried implementing VLAN on them.
My idea was to use CRS112-8P-4S-IN, to have 3 VLANs, "Guest" "Corporate" and "Base".
I would use one of the SFP ports as an uplink to ISP, other 8 would be configured as follows:
eth1,eth2,eth3 - Base Untagged, Guest Tagged, Corporate Tagged - UniFi APs, manage them on Base VLAN, and broadcast SSIDs with corresponding VLANs
eth4,eth5,eth6,eth7,eth8 - Corporate Untagged - PCs and printers

I even tried setting up with RB760iGS and CRS112-8P-4S-IN. Both are on RouterOS 7.2 (Stable), after 3 days of watching youtube videos and reading this viewtopic.php?t=143620&sid=510e15fbfe04 ... 22910312fb I just can't get it to work.

All help is appreciated, also is there something like Cisco Network Assistant, but for MikroTik?

I even tried setting up with RB760iGS and CRS112-8P-4S-IN. Both are on RouterOS 7.2 (Stable), after 3 days of watching youtube videos and reading this viewtopic.php?t=143620&sid=510e15fbfe04 ... 22910312fb I just can't get it to work.

All help is appreciated, also is there something like Cisco Network Assistant, but for MikroTik?

I have never used Cisco Network Assistant, I used Cisco SDM around 10 years ago, but I don't remember it having support for vlans, but that was also before I had used vlans much, and it was really more focused on the ISR routers, not switching. But perhaps it did, and I just didn't attempt using the feature.

Coming from the vlan-aware switch0 on an EdgeRouter-X to vlan-filtering bridge on hEX S was quite a culture shock at first, but once you wrap your head around it, it makes sense, but I am not sure what vlan background you have, an what equipment you have used vlans on before. The UniFi way of doing things is another paradigm as well.

This post has the link you looked at, but also three other links I found helpful. The official documentation is pretty good, if you have a technical vlan background. It does assume the reader has a good understanding of the fundamentals.

Have you setup UniFi access points with multiple SSIDs with another router? If so, let us know, we may be able to compare and contrast how vlans work with the vlan-filtering bridge compared to what you have used.

Mind sharing an /export of the minimal config you have been attempting to get working?

What other vlan-aware networking kit do you have? Do you have an linux pc or Raspberry Pi that you can load the vlan package on as a test client that is vlan-aware?