To follow up the issue of “Bootloader invalid package 0002”, and actually, it could be 0080 or something else.
In short, you will need to re-flash the firmware and you will need a serial cable. I found the cheapest one here:
And it's just RMB 17! The quality is excellent, way better than the ebay autostar serial cable I got a few years back, and it's much cheaper as well. I got it on the following day and it is from Shanghai to Hong Kong!
And then you will need a serial port, i.e. RS-232, but then it's really hard. I searched through all the PC that I could access but none of them got a serial port. So, I took the plunge to buy a USB serial adapter. I have experience on that with my Autostar before, so I got this one:
And it comes with a long USB cable too! This cable will work with my Lumenera 075M, too.
From that taobao site, I realized that Chinese firmware is available, so why not?
And we still have English with this firmware.
It's just quick and easy! I might want to use a bluetooth serial module from ebay some days later so that I can control the Nexstar with my mobile phone remotely!