MOR404, You typed that the problem occurred the second time you used the car after some months(?) of being laid up... which MIGHT suggest the lay-up was not the issue, or the conditions prevalent during storage..?
HT leads can and do fail though not with any regularity. Not too expensive or complex to replace anyway, have you checked in the dark for HT leakage..?
Perhaps a furl issue as fuel can degrade over lay-up or you fuelled up with some poor fuel, which is unusual though possible.
If your engine is of the sonic idle type, find out how that aspect operated as I have no idea.. I am pre-sonic idle..(-:
Good luck.
