Hey husam, cheer up!
I took a short look at that project you are currently on, and here are my humble suggestions. Note that i’m not experienced in electronics so don’t blame me if you burn your computer down.
The fuse. Use your common 250mA fuse or no fuse at all. It is for protecting your USB port from a shortage. I have never used a fuse in my usb projects. Just make sure not to short VCC to GND by chance - it is a bad idea anyway. Also the reverse current protection diode is optional.
Zender diodes. As far as I understand, they are for clipping the signal voltage to 3.6V. So try your 3.9V and 3.3V zender diodes. I suggest it should work.
The most tricky thing is the Atmega controllers. If the author says it won’t work with the ones you have, it probably wouldn’t. Just try to search online shops: i’m pretty much sure there are some which do shipping to Iraq.
Hope that helps.
Good luck to you!