Air carrier Captain reported confusion with the poorly marked lead-in lines for a gate at BKK/VTBS airport.

Narrative

I'm writing this report more to highlight a potential safety issue in BKK; rather than to highlight any particular flight.On the flight this report is filed under I elected to perform the walkaround while the FO set up the aircraft. An employee on the ramp; there was language difficulty; addressed me directly about a concern he had. He said that recently 3 company aircraft had lined up on the wrong lead-in line for their gates. Again; a bit of a language problem; but he certainly picked the right guy; as I had done that on my first trip to BKK. I understood what he was talking about and gave him my take; said I'd write a report; so here you go.This applies to the SAT-1 Apron. As you approach Gate XX from the east on Taxiway T19 you see two Aircraft Positioning and Information System (APIS) boxes; [Gate] XX and XY; with [Gate] XX being closer to you. It appears to line up with a dashed; dog-leg lead-in line that is also closest to you. We discussed. Layout doesn't match the Airport Moving Map (AMM). Turned in; realized it looked wrong and stopped. Waited for manual guidance to the proper line; and had plenty of space to do that.In hindsight there were other clues; and guidance in FOM and bulletins and 20-9 pages that should have come together. And yet...Here are my observations:The 10-9 AMM page only shows a single lead-in line; unlike; for instance; LAX. We may not use the other lines in BKK but it is a surprise when you come upon them. The 20-9 AMM page does hint that there are other lines.The ID numbers for many of those lead-in lines; painted on the ground; are [expletive]. The paint on some is chipped up; making them hard or near-impossible to read.The lead-in line we initially bit on was dashed; which in some of our operations delineates a widebody line. When properly aligned with the [Gate] XX APIS box; there is the dashed dog-legged lead-in to my RIGHT; and its APIS box ([Gate] XY) is to the LEFT of the one I'm using ([Gate] XX). It is marked correctly; however. It is also angled to the right; so it's 'beam;' as it were; crosses in front of the [Gate] XX APIS. Can't see that from a distance. I believe this is the crux of the problem; if other aircraft are lining up incorrectly. But I don't know those stories.As you approach from the direction we did; you get the illusion that the illuminated [Gate] XX APIS is in line with the lead-in line for [Gate] XY. You are not prepared from the AMM that the ramp is not simple. The APIS chevrons told us something was off. And there are TWO chevron windows; one for Captain and one for the FO. New to me but mentioned in the FOM. Could add to confusion. Obviously the ramp personnel sensed this was a bigger issue. Yes; there are clues; but I think human factors are more at play here; if multiples of aircraft are behaving the same.Perhaps some of this info should be incorporated into the current BKK briefing or the upcoming 10-7.