The mounting solutions supplied with the later V2 model initially consisted of small 3D printed blocks that were screwed on to slots in the A600 motherboard (intended for the hard drive caddy). The motherboard is removed from the A600 and the screws are put in from underneath into the blocks on the top side then after reassembly and connection of the Vampire it can be screwed down on to the blocks. Later this was changed to a bolts, nuts and stand offs solution that still needs removal of the motherboard to install. These were provided with the Vampire 600 V2 by kipper2k who made most of those boards. Kipper2k is no longer involved with Vampire production but may still have some mounting kit parts. Majsta is putting the Vampire 600 V2 back into production so maybe he will be sourcing mounting kits for that. Other people have come up with their own DIY solutions like glueing a bolt to the CPU or 3D printing mounting frames (not sure if one has been designed for the V1 but here's an item about a V2 version http://www.amiga-news.de/en/news/AN-201 ... 62-EN.html
I don't think there are any jumpers to set on the Vampire (all the pins are IO headers).
I think some cores may need certain versions of support software for completeness and compatability.
If you want to change the core I think you will need a USB blaster, the appropriate file and the Altera software to download the file from a PC to the Vampire via the USB Blaster.
Hopefully somebody with more knowledge than me can help you with cores once you have the Blaster but bare in mind that the cores from the Apollo team for the V1 were very constrained by the small FPGA on the V1. If it has an Apollo "Phoenix" core on it already there's a good chance it's up to date as development was abandoned a long time ago due to those constraints. The original core of the V1 was a version of the TG68 softcore .