I'd like to suggest two things. First, if you don't have much money to put into a decent AVR ISP programmer, just get the cheapest one from eBay. There is no need for HV to program fuses unless your chip refuses to be programmed via ISP, and it beats trying to get Arduino to do something that it doesn't like doing. Second, "garbage text" doesn't tell much. Images could help a bit in such cases.
I'm a PIC programmer with PIC tools, if this was a PIC based project I'd have it working by now. I've even considered porting it!
Here's the rub, there are several modifications to the original design, crystal, LCD- GLCD display, voltage reference, HV zener, rotary encoder, Mega8, 168, 328... the list goes on. This makes it a little daunting to anyone unfamiliar with AVR programming. Worse yet are 99% of the programmers for ATMEL are the LV serial variety, so if you mess up the fuse settings well that's that. I've messed up a couple of 328p when trying to set the fuses. This command -U efuse:w:0xfc:m would set the lfuse to 0x04 go figure.
I think the Arduino is a nifty bit of kit, simple IDE to setup & install, cross platform, and a no brainer workflow. On the other hand I have no real interest or use for ATMEL micro controllers or wish to blow $85 CDn on an AVR Dragon for what will amount to a one off endeavour. I simply want to upgrade a banggood clone to 1.11k or possible 1.17m (is one better than the other?). I'm using a bit pirate as a programmer. I might pick up a USBTiny programmer as they're supposed to work with OS X.
Seems I'm not the only person that had problems upgrading the firmware on an MK168. Based on this thread alone looks like most folks don't get it working without some help.
I've tried the files in the UK & EN directories (EN english? UK english? err what) FW 1.11K latest from this site.
http://www.avrtester.tode.cz/index.php?p=firmware But without knowing what options were chosen it makes it tough to know if it'll work.