ok, it sounds like your choke is not working right. double check your slides. when they are in right, yolu will see the dots through the windows @ wot. the cable retainers are slotted on the bottom one side to allow air through the hole in the slide. check the choke jet. it's @ the bottom of one of the bowls through the hole that slips around the tube coming out of the chokeside carb, and looks like the pilot jet. if it runs good without a bog once it's @ operating temp, then that is normal. if it's all the time, and it keeps wanting to go richer, then your main or pilots may be off. try larger mains. if you pin it and it bogs, but picks up in a second or 2 while holding it, then it's a lean hesitation on the mains. i was actually jetting my procircuts last night, goin through the same thing, but it got too late to make noise. i guess pro-circuts are thirsty pipes. 300 and still lean, where 290 was just @ rich limit on my fmf's 15 degrees colder. if you get it running a little better, go do a proper plug chop to check the mains.
the idle screws really wouldn't leak as they are before the sealing rear of the slide, and the locknuts would keep it sealed anyway. did you cut the nipple and file it flat? 1/8-1/4"