How to build a DLL from previously parsed and modified files?

Question

.NET

There is an old program for graphics, I wanted to update it. Because the program is blatantly hacked and sold to us as "Own" I can't update it, etc.
In general, the essence is simple, I disassembled the dll, replaced the files in it (left the names the same), but here's the problem - to assemble. Are there people who care about mental health? who can tell?

Answer 1

dotPeek has a magic "Export to project" button that appears when you right-click on the desired build.
After exporting, you just need to open this project in Visual Studio and build it again, after changing the files that interest you.

Answer 2

https://github.com/dnSpy/dnSpy/releases
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