I think I have been really stupid!!

First stupidity:
I bought a Gotek drive on ebay from a russian guy - with a label on it, saying: Download the manual and FW update at hxc2001.com
Wish I had bought the original from amigastore. Hindsight is always good.
Secund:
So, I went into the site, and searched for firmware. Because the Gotek drive has a USB stick, and not an SD card slot, I thought I should download the HXCFEUSB_HFE firmware (HXCFEUSB_HFE_V3_0_8_2a.upd). So I did, and updated the drive.
I start in the menu, I can select files into the slots, but from there I just have errors.
- My Amiga 500 (Can load part of a floppy, then it freezes)
- My Amiga 500 plus (Starts to load, then it resets)
NOTE: Have en NOS floppydrive, and from that both Amigas runs like a charm.
I realized that something was wrong, so I tried to download the currect firmware (I suppose it's the HXCFE_V1_8_2_40.upd). But trying to upload the firmware gives me an error 5 (Bad UPD File header! (bad file))
What to do? Normally I NOT that stupid, so please bear with me.