Combat Patrol Campaign, need help with fluff...

Greetings all.

I am in the creation phase of a Combat Patrol campaign that leads into a massive Apocalypse battle, for our local group "Brothers-In-Arms".

Here is the premise:

All Combat Patrol (40k in 40 min) rules apply, with the following addition. Each army is given a max 100 point reserve list that can only be swapped out between games. I have set the campaign on the planet Faustus Secondus (a planet of my own creation) which sets centrally in the galaxy. My initial thoughts were that the planet contained the remains of an ancient civilization and within that was discovered several pieces of very important Xenotech. Each race has sent small insertion forces (combat patrols) onto the planet in order to build and maintain control points thoughout the planet, with the intent of gaining a foothold which would allow them the resources to launch a massive worldwide assault. (this would be the grand battle between the top 2 victory point holders after 6 games)

What I need from you as a community is background motivation for each of the races on why they would take an interest in this planet and it Xenotech.

Thank you in advance for all your help. Each reply that contains a viable motivation will be acknowledged in the campaign notes and made known to the members of "Brothers-In-Arms"

JP