This happens a lot I believe looking at the "Modding" Wiki. This is how to SOLVE the two issues.
No texture files Only numbers
When I click on a file UAE CRASHES
Let's deal with the non texture files first.
This happens to me and I don't think there is a real way to fix it but I'm sure there is!
First of all, try closing down and reopening the UAE.
Second of all, if this does NOT work try uninstalling and reinstalling UAE if this does not work restart your pc. IF all fails then I do not know how to fix your problem.
Now, let's deal with the easiest issue! The crashing issue.
You will have texture files and this is why it'll crash
follow the steps below to solve your problem.
First, you should (if not deleted) have a file somewhere on your Desktop or wherever you extracted your UAE files, a file titles UAE click on it.
Once it opens you'll have multiple files and what you want to do is select one called Texture Plugins.
Inside the folder, you'll have two other folders called DX90c and NODX you want to open up NODX.
Inside NODX is a file? Called Texture.dll you want to COPY not cut or delete this file and you want to go back to the "starter" UAE file.
Now, with the Texture.dll copied, you want to go to the file named Plugins. Inside Plugins is the folder Default/
You want to PASTE the Texture.dll inside the DEFAULT file. You'll get a message saying that the file is already in the default. You want to click REPLACE FILE.
Now, close down the folders and open up UAE it SHOULD work