I don't understand your first question... can you rephrase it?
As far as your second, I'm no clan fan, but I haven't found the problem you're outlining. Clanners don't need to own their 'mechs, so points don't need to be spent on that. I don't know about the fluff angle on specific clans.
Speed of XP gain is entirely within the GM's control. That includes downtime XP gains. I'm not really seeing a problem here.
The conversion between personal BAR armor and Tactical Armor is covred in the Companion, but BA/PA(L) armor is an exception. You'll find the conversion for the Nighthawk in the same table with the Elemental.
As for your last question, I recommend Victor_Shaw's threads on his MW2E conversion rules. He's working out how to make the random event rolls work for that.
And welcome to the board! 
Thanks.
I have to apologize, I do not good with english for independent speech, I have to rely on an translator and this is not ideal.
The first question is the most critical in fact, you know perfectly well the firing range in this system. Problem - I play online where the table size is limited by the settings and all this will have to be adjusted manually, I usually used a 50x50 table and it was quite a big arena for say, DND, Pathfinder and the World of Darkness, but here we are and I have no idea how much it should be a giant map to use AT LEAST medium range for rifles, pistols work well in 50x50, find a suitable map on the Internet, so it's not an easy job, especially if you don't have money, and then you also have to figure out how to stabilize the size. The situation when the characters are conditionally sitting at the table "for battlemechs" was already the size, not much of a problem, but it delivers trouble sometimes.
In general, yes, can you advise something with the sizes? Even at 50x50 you can get confused and making more of them will be just crazy. It can be bigger but orientation on it hard even on 50x50
Second question.
Clans don't own their mech, yes.
But this does not negate the fact that they must be bought from experience, but this is the least of the evils.
What worries me is that Slow Learning is one of the strongest penalties in the system and it is generally mandatory to buy it, clans have slightly higher stat requirements for their fields and paths and as a result, there is rarely anything left for edge, charisma and intelligence. Freeborn suffer less, but here's the paradox, charisma is obviously needed for politics and roleplaying the leader, the problem is, Charisma is the most suffering characteristic for Clan Trueborn and Freeborn cannot participate in politics. I even got the feeling that if you want to create at least a little bit of a valid "future leader", you have to be a meme like Nikolai Malthus with -500 in Arrogance and other Clan penalties. I just got this impression, and it annoys me, especially in the future to make a Clan character for the company with the characters of the Inner Sphere.
I know that the control of experience hangs on the GM, I am interested in other people's methods, I am not a supporter of the invention of the bicycle and I prefer to turn first to someone else's experience.
The table for the whole BA is generic, I know, but I'm still not sure exactly how it works, the amount of armor in TV = BAR Armor for the BA table, right? The night hawk has 2, so its BAR is 4/5/6/5?
And thanks again, honestly, when I saw that another topic with a difference of only three hours was directly actively discussed, I was afraid that I would not even be able to discuss it all.
