I am in the UK. I purchased a CTC 3D printer last week. I have used it to print off some items I designed using sketchup with varying success. To do this I had to commit my PC to the task because if I did anything else on my pc the printer stopped, giving a message 'serial error'. I tried several times to print things but at some random point it would just stop with an error message 'serial error' with the display on the printer displaying gobbledygook. I tried with another pc I have as a standalone. It did a 4 hour print yesterday with no problem but when I started another print it failed with 'serial error' several times.  I would like to print from an SD card as this would free up my computers. This seems to need an x3g file. The printing I have done so far has been from gcode from my directly linked pc. The printer came with an sd card from which I got replicatorg to make gcode files from stl files from sketchup. I think I need makerware software to turn gcode into x3g. The sd card that came with the printer had makerware software on it but my pc won't download it. I went on the makerbot website and downloaded their latest software but it disappeared. I turned off my MacAfee virus checker and downloaded it again to no avail. I would like to know how to download the makerbot software to make x3g files bearing in mind my pc runs MacAfee.

Set your browser so it downloads the file to someplace like the desktop where it is easy to find. Or download it to another PC then put it on a thumb drive.. You could also buy Simplify3D as it works with these printers as well and well send or save the X3G file to the sdcard.