1.

So it says you can have 5 legacy moca clients and 2 4k clients(I know total of 8 but not my point). So I am guessing that you can have 7 total streaming at the same time if you have 5 plus 2 correct? You could have 6 legacy moca clients but only 5 will work at once? What if you had 7 4k clients could all 7 watch non 4k content at the same time or only 5 ?
7 streams total, only 5 can be MoCA 1.0 (C31, C41, C51), only two can be 4K, up to all 7 can be wireless or MoCA 2.0 (C61, C61K (non 4K), or C41W)

2.

It doesn’t really say but let’s say you have a reverse band lnb and you get the correct lights. Do you still have to use the handheld app ? Might be a dumb question and I know when you are able to connect with the app from the instructions on the leds but is it always necessary ?
The only time the app is really needed is if you are doing a D2Lite or International install so that you can use the app to tell the HS17 what type of LNB is connected to the SWiM module. In all other cases you are likely okay to just hook up a client.