I'm sorry if these questions have been asked before (i'm pretty sure they should have been answered already), i tried to find the answers, but this thread is alreay more than 700 pages long, so it was TL;DR  

I tried to setup a p2pool node, rented some hash on miningrigrentals and started playing with the setup, i ran into the following questions:

• I set a 1% pool fee, meaning that if somebody on my node mined a block, i would get a 1% cut... Seems fair. But i've also seen a node setting a +90% fee, does this mean that he gets an equal cut when somebody on an other node finds a block, but when he finds a block he can keep +90% of the block reward?
• i can setup my node so it doesn't broadcast new transactions. If i do this, can i put my own (secret) transactions in a block or do the other nodes also have to know my transactions? I know the chance of hitting a block by yourself are astronomically small, so it's just a theoretical question.
• Can i prioritise my own transactions, so that if a block gets mined on my node, my own transactions have a better shot of being in this block?
• If i find a share at a time when there is a dip in the p2pool network's hashrate (so the diff of the sharechain is lower), does this share have an equal value to a share that is found at a time of high hashrate (so high diff)?
• I tried a setup where i merge mined several coins, the log didn't show any errors, but for some reason i didn't find a single share on the BTC sharechain anymore (at the time i should have found 6+ shares, but i didn't find a single one... This could be due to variance, but the odds of this should be small). Is there a potential pitfall i missed when setting up merged mining, or was i just very, very unlucky?