Important settings.
vmmaker.ini
monitor_specs0 15000-20400, 54-62, 9.162, 4.856, 14.775, 0.190, 0.191, 1.018, 0, 0, 288, 448
monitor_specs1 30000-31999, 54-56, 5.209, 3.855, 6.564, 1.227, 0.033, 1.061, 0, 0, 500, 500
monitor_specs2 30000-33600, 57-62, 5.209, 3.855, 6.564, 0.452, 0.032, 0.678, 0, 0, 492, 540
monitor_specs3 30000-34000, 57-62, 3.396, 2.819, 5.767, 0.390, 0.032, 0.487, 0, 0, 512, 540
monitor_specs4 39001-42000, 48-54, 6.141, 3.392, 1.632, 0.063, 0.209, 0.627, 0, 0, 768, 798
monitor_specs5 42001-49000, 55-62, 1.451, 1.284, 4.451, 0.063, 0.209, 0.627, 0, 0, 768, 798
mame.ini
crt_range0 15000-20400, 54-62, 9.162, 4.856, 14.775, 0.190, 0.191, 1.018, 0, 0, 224, 288, 448, 576
crt_range1 30000-31999, 54-56, 5.209, 3.855, 6.564, 1.227, 0.033, 1.061, 0, 0, 480, 500, 0, 0
crt_range2 30000-33600, 57-62, 5.209, 3.855, 6.564, 0.452, 0.032, 0.678, 0, 0, 480, 492, 0, 0
crt_range3 30000-34000, 57-62, 3.396, 2.819, 5.767, 0.390, 0.032, 0.487, 0, 0, 496, 512, 0, 0
crt_range4 39001-42000, 48-54, 6.141, 3.392, 1.632, 0.063, 0.209, 0.627, 0, 0, 640, 768, 0, 0
crt_range5 42001-49000, 55-62, 1.451, 1.284, 4.451, 0.063, 0.209, 0.627, 0, 0, 640, 768, 0, 0
These may not be perfect. I didn't do any interlaced resolutions, I disabled interlaced in mame.ini because I thought it looked better.
These could also use some work, on the 240 and 288 modes, square objects become a bit elongated as they pas throught the middle of the screen. I've been fighting this issue the most. With the standard 240p timings, objects reaching either side of the screen got thinner. Really annyoing. It's probably because the BVM doesn't officially support 240p so finding exact settings are a little difficult.
Also, All these settings are configureds wiyth 16:9 on the monitor turned OFF. All these resolutions should end up lookin 4:3 ratio but you will have to do the on screen aligignment on 240, 400, 480 and 768 to make sure they are all set right. I used Arcade OSD to switch the resolutions and check geometry.
You'll also get a nice 1024x768@60hz desktop. Run hyperspin at this resolution. Personally I use GameEx but it shouldn't make a difference.
I'm attaching all the files you should need.
I know some of these mode lines can't be dead on so whoever can help with that, great!!!