well you still have the low fuel pressure thing to get up to spec it could be the regulator or the pump until you get your pressure up I dont think your injectors will be giving you a good spray of fuel. There is some test you can look for in the Haynes repair manual that may help localize the problem. best of luck.
ps. After reading your post over again you said you pulled a vacuum on the regulator and it held steady at 25 inchs of vacuum that may only that the diaphram in the regulator isnt busted but if the seat on the fuel side is damaged it could still be letting fuel go back to the fuel take and not building pressure. check out the hanes repair manual for its trouble shooting of the system it will help.