Sorry to hear about your troubles, but yeah, your squish/port timing/compression is way way off.
Try using just the dykes ring for less friction and flutter, which will yield higher RPMs. Gap it between .009-.012". Doing this for me helped me (not sole contributor) gain +1500 RPMs.
Give the cylinder a run down and get rid of any inconsistencies and asymmetrical ports. My Gila had a nice hump in the ex port (now gone/polished) and had asymmetrical intake and exhaust port openings (widened left side of ex and right side of intake, 2mm each. Yours may be different). Give it a good chamfer and move along to the gaskets.
Run the Gila head and Gila gaskets to start. Be sure to match up the base gasket to the transfers since it's most likely hanging over them a bit.
See where the piston sits at BDC - if it's flush with the ex port, check squish. If not, adjust until this is achieved, then check squish.
If squish is between .8 and 1.2mm, check compression. If not, adjust head gasket until this is achieved, and then check compression.
If compression is in the 155-175psi range, move to timing. If it's too high/low, look in to getting the head milled and re squished to keep it kosher, then move to timing.
Time the bike between 2 and 2.75mm BTDC. 1.8 is WAY too low for the HPI Mini. Keep an eye on temps/performance and adjust if necessary.
And mess with your variatior weights. Easy 60+ after all of that.