Hey mate,
Welcome welcome!
I'll try to answer what I can and provide some links for further viewing/reading.
1) So, I've not let the AI be in charge of my recruiting so I cannot speak to how good or bad of a job it does but let's just say that it will not be as competent as a human player - there is a thread here where I've detailed a lot of stuff about the different mechanics from my experience in the NCAA mode and there is some other good stuff in the thread too from various discussions, I'd give it a read -
https://forums.ootpdevelopments.com/...d.php?t=341923
also, here is a thread on reddit where I went into a lot of detail about how the season timeline works and what you should do at each stage -
https://www.reddit.com/r/FranchiseHo...luj/?context=3
Lastly, I'd advise watching the first episode of the official playthrough, Jeff explains how to set up a watch list of players who are not committed to other programs for you to approach on verbal commitment day, he also shows you where to find players who have previously verbally committed to you and are the ones that you should target on National Signing Day (it's in the unsigned drop down of your teams options).
So that's the recruiting stuff.
So, scouting, it's a bit abstract in FHM as it's not like other games where you can just order a scouting report on a player at your desire, it is done by having players fulfil the criteria set under your scouting priorities. So really the most effective way of having someone scouted in good time in FHM is to add them to your 'watch list' (that will be shown in the official playthrough.)
The advantage of adding your target recruits to your watch list and having them scouted is so that you can have the best idea about who is as good as you see them to be and who looked good at first but eventually falls off. Also it provides you with more detailed information on the scouting report tab, which shows things like a player having hidden volatile potential but also if they have an attitude problem and could cause locker room issues and also if they're a dumbass and are likely to not qualify for you if you're playing as one of the more academically elite programs. So it's important to scout the players who you feel are relevant to you.
There is some nuance to the way scouting grades are shown at the side of the players row, here is the link to the manual page that explains it -
http://manuals.ootpdevelopments.com/...&page=scouting
It's also worth bookmarking the manual and searching for stuff there if you don't understand it at first. It's got explanations about college stuff and recruiting too should the other two threads and video I've already linked not suffice.
In terms of monthly spending, you may notice that when you allocate a decent amount of scouts to any region it still does not fill the score up to /20. That is where this monthly spending comes in, I tend to have this set to full (where I can, points permitting) until all of the recruits in my watch list are showing as (Aa or Ab or Ac - The first letter indicates scouting accuracy, the second indicates the likelihood of them fulfilling their potential). So that I now I've got the most info I can about them, it does degrade over time though, so I never drop it down all the way to 0 or - or whatever the bottom option is until after both recruiting activities are done and I know that I will not need to be fully scouting anyone until the following year, then I can let it slide a bit.
POST GAME ANALYSIS
So, This message always comes up, I'm not sure what, if any, coaches ratings play into it but it's mainly attributes to players being out of their 'desired' roles, so if a guy thinks he's best as a counter attacking forward and you're playing him as a Dangler, he will get that message. This is as far as I know, I tend to ignore it if the player is playing well and I only sim games anyway really. So it's worth experimenting with player roles for guys to see if it goes away. If anyone else knows coaching ratings that can help with that then please feel free to correct me.
Last question,
About scouting outside of the US, I guess it depends on the 'pull' of your program? There is info regarding that in the other threads, so if you're a small school in the ass end of nowhere who's got a terrible record and low prestige (see Market Size) then I guess you're not gonna be landing hot shot foreign recruits, not to say it's impossible, you're just more likely going to be successful sticking to guys who are instate or close to your state (there is now a state filter available apparently though I'm yet to use it - so that will make it easier to find these players). I'm not sure of the effect of turning off foreign leagues too, perhaps Jeff can interject with something on that.
Either way, check out all of those things I've linked and see if they are any help!