This isnt going to be easy, and I'm not really the best person to educate people about trackers (it's been a long time), but what you are after in a tracker simply doesn't exist (metronome, typical MIDI piano roll).
The format of tracking has closer resemblence to step-sequencing samples at varying pitches vertically, than what you have come from (piano-roll based horizontal sequencing). In a tracker, the step sequencing is done vertially in the columns of a tracker (channels). In these columns, (unlike midi) you can only trigger 1 sample at a time, but this makes perfect sense (and not a limitation) when you relalize that those scary looking numbers (initially zeros) next to the notes in the column can be used to manipulate the sample sound in realtime.
By default, you start of with 64 lines (0-63) which is divisable by 4, so you stick in a drum kick sample at every 4th interval, you should (if you did it right) end up with a pattern that has a perfect 4/4 beat. There's your metronome.
You can put different samples in the same column, you just can't trigger those at the same time. So between your kick sample you can put a hihat sample, and so on... Obviously if you want to put a snare in you would be best off putting it in an extra channel in parallel with the drum kick.
Overall the principle is really staggeringly easy, it's just one of those things you have to have a Zen moment with, you know, like not seeing the Matrix for what it is until you've had the red pill
Belive me, once you've cracked it - it's amazing. It will just take a lot of patience and a willingness to learn, and also a willingness to drop your expectations, as to be quite frank - coming from something like Reason and FL seems like a bit of a backstep if you are intending to go further with proffesional music. Modules are indeed still execllent but you will be sorely lacking your comfort-tools that I believe many take for granted in those studio applications.
Well, welcome to the Mod Archive, and welcome to the world of tracking, if you stick around I'm very sure you will find it an awesome facet of the music scene.
One final piece of advice, I suggest you grab a tracker like Modplug, or Milkytracker - load up some modules and then _watch and learn_. Thats how I did it.