Cleaning up old plate holders and camera

[awty]

Hi all
The postie chick bought me a big cardboard box today, with an old WERTH & Co FRANKFURT 24 x 30 cm, with 3 x plate holders. Everything looks to be there just needs a clean up.
1. Two of the plate holders have ply wood inserts, I assume they are for placing film in the frame and then you place the ply over the top? and they are removed when using plates? They arent painted, should they be?
1. (d) almost forgot, best way to clean the white gunk off the middle black plates? I think I will take them out and clean and repaint.
2.The other one has 2 x very sticky glass plates, I assume they are just left over collodium plates?
3.The slides dont slide all the way out, I take it that thats normal, is there something i can use in the way of a dry lube to get them running smooth?
3. (b) the dark slides seem flimsy on the bottom, but looking at the way they are constructed looks to be on purpose, should I try to stiffen them up or is there a reason?
4. The camera movements could do with lubing as well, same deal with dry lube?
5. The leather handle seems to be missing and would like to replace, is someone can link me to a way to make one would be great.
6. I would like to make a lens board holder to take a 15cm (6") board if some one can link me to a picture of something similar I can make, that also will be great. Would like something I can mount ontop of the existing with out too much trouble.
Im not interested in doing a full referb just a tidy up to make functional. Ugly camera make the best pictures. I have plenty of skills and tools.

I will be using it for field work with xray film for the time being and eventually plate photography when I learns me how.

Thanks appreciate any help.