152 must snap from side to side via the tension of 151. The main lever 204, must never "push" 152, but only be guided by 152 once 152 is in the right position.
In the cam guide I showed how to disassemble and rebuilt the cam. Because 151 is so "insanely" small, you might want to lasso the thing prior to disassembly. Take a fine sewing thread and work it around the spring with a simple knot --leaving something like four feet of thread to find it later--, and carry out the cam cleaning as outlined. It is a good idea to just give that "w" spring a bit more width by stretching it a tad. To replace the spring onto the cam, use a dab of lube in each socket (cam and 152). Remove the thread, place spring 151 into the cam greased pocket and line up to receive the pocket of 152. Hold 152 in place till the c clip (149) is placed. With the grease in these pockets, the chances of 151 taking unwanted flights into never-neverland is greatly reduced.
192 must be tight. There is enough flex for 188/204 to rotate because of the bow in 190. make sure to place a dab of grease between chassis and 188. There should be three or four dimples on the sole of 188, which will ride in that grease.
Pay special attention to the lubing of all the levers and parts that bolt 200 runs through. These are 200,199,186,255,254,248,247. They must have alvania and molycote in proper sequence to allow the Start/Stop switch to return to neutral position when the "Manual" position (with 252) is selected. This lube sequence can be seen in my pictorial of the 1009 and 1019 on my website.