Tsumi

There has been a new windows 10 update rolled out recently, that might have been the cause (I haven't yet updated). Other than that, have you changed any configurations or customized the program before? Meanwhile, you could try using Translator Aggregator with JParser, it gives a similar experience to Chiitrans for the Furigana. It also has access to translation service sites like google and bing and several others. I'll try updating Windows later and let you know if it was the update which caused it to stop working.

There are chances that VNR is not able to find any text from the game. Did you check to see if VNR has found any hooks for the game on the Hook Tab? If not, VNR won't find any text at all and it won't show the text window. You might have to wait for someone else to input a Hook code into the database before you're able to read through VNR, or you could find one yourself. As @Black99 has said, you could try using another program. I do also recommend using Textractor; it auto-hooks games just like VNR does and is currently maintained.

What exactly did you try doing? Did you try setting the compatibility mode in the file to a past version of windows? Did you also try renaming the folder?

The game engine might have changed a bit as time went by, and in this case, ITH manage to work with the new versions and not the old ones. You might need a specific code for it or you could try using another program (which already come with new methods and codes). People usually use VNR, it's a respected program, though personally, I'd recommend using Textractor as it's much simpler and less weighty and still in development.

As a matter of fact, Textractor does have transparency... you change the alpha of the background colour. https://github.com/Artikash/Textractor/issues/132

For each game, its own tool. If you could say the name of the game you're trying to cheat at, it would make it easier to give you hints of how to begin finding your own values, but as SkraalQ said, the simplest way to find a value which does not change places in memory is looking for it every time it changes and changing value types through trial and error. Did you attach to the game? Also, which game were you trying to cheat at, once again.

As for SpoilerAL, you usually download an SSG file from somewhere with the addresses of interest already present on the file, and all you have to do is go through the table and manipulate the values.