So this is what I've been doing for the past two weeks.
The dungeons is made of styrofoam...I used "wall paste" (I don't know the word in English...put you normally use it for fill in and smoothing small cracks and holes in the walls before you paint the wall) to cover it before painting it with acrylic colors.
The furniture & shelves I made using 3mm thick cardboard...then used the same wall paste to imitate the old wood texture before painting them. Floor...pretty much the same thing...for that I used furniture paint because I wanted it to be a little bit shinier.
The doorway...frames...again thick cardboard...the "glass" is just see through plastic that I painted with blue glass color and then put the grid on top of it (just black thin cardboard slices) There is no hole behind the door. I made the light-effect just using this cheap battery operated led-set and using aluminum foil behind it. It really looks like it's deeper than it actually is!
The torches...I used the same cheapo led-sets...the torch is the last led on the set...the rest of the lights are over the "roof".
All the glass vials, bottles and test tubes...bought them from etsy and then clued small labels on them (oh joy!) and filled them with different spices and stuff. Papers, books, newspapers on the tables...just printed stuff from internet and made them into books and stuff.
The candles and the mortar are fimo clay...and the figures too...I've posted them earlier here....but now they have a home. :0)
This has propably been the most fun project I have ever made...labor of love, I would say. My own home was a reaaaal mess during the project...I suspect small pieces of styrofoam will be found even decades from now.
Scale is about 1:10