[Dabhand16]

I also have a Mini Trekker AW, and i have to say when used as a rucksack, it is excellent. However, when carrying it by the top handle, the straps are all over the place and they are a real pain, dragging on the floor, getting tangled in stuff etc.

I'd consider a top-loader, or maybe a cheap metal or plastic briefcase style case similar to those used for DJ/audio kit/etc. Line it out with HD foam and you can make your own partitions.

Try Maplins.