Ok, so briefly how to take H7 apart:
!!Warning!! We do not recommend taking apart our devices. If you facing any issues, reach out to your seller within warranty or directly to us if the device is out of warranty. Proceed with this only at your own risk.
1) Take out both wheels. Simply pull them off, they are hold in place by friction and plastic spacers.
2) There are two brass rings around the volume pots, unscrew them.
3) Simply lift up the front panel.
4) Now the main boards can be pushed out of the aluminium frame. Push carefully from the front (display end), the boards will come out of the rear(RCA connectors end), with the back panel still attached.
!!Warning!! The PCB is connected to the frame with one cable for the antenna, at the rear and on top side. It's a small coaxial connector, disconnect it before pushing the board any further.
Now you have the boards out of the device and can do whatever you want with them.
For the batteries, they are hold in place by lines of glue connecting them to both of the boards and they are soldered in place by two posts. Exchanging them is fairly easy, but you need some basic repair skills.
No, it's only receiver.
You mean the velvety pouch that comes with the H7? I use it with my H7 and even with M9 and haven't seen any problems with pain coming out of it. But I didn't tried to soak it yet.
Insides of H7 are not glued, they are just fitted, with some additional foam on the edges.
We always try to help users if they decide to repair their device by themselves. Not sure why you have such a pessimistic view of us.