COULD&WOULD please help

[ridskf]

What does the words "could" and "would" mean grammatically in these sentences? This has been haunting me for a long time so I hope you guys can help me out. Thanks in advance!

A German historian said a distant relative of Adolf Hitler 1) could sue the state of Bavaria for royalties from the Nazi dictator's book Mein Kampf, but the retired Austrian engineer said he wants no part of it.

Werner Maser told Bild an Sonntag that Peter Raubal, whose father was a nephew of Hitler, 2) would have a strong chance of winning the copyright from Bavaris.

"Peter Raubal is the only heir of Hitler that I know of," Maser said. "As the closet relative alive, he 3) could claim royalties from Mein Kampf. Raubal 4) would have to sue Bavaria. I am quite certain he 5) would win."

Bild an Sonntag said royalties 6) could be worth millions of Euros.

[5jj]

A German historian said a distant relative of Adolf Hitler 1) could sue the state of Bavaria for royalties from the Nazi dictator's book Mein Kampf, but the retired Austrian engineer said he wants no part of it.
The relative had the theoretical possibility.

Werner Maser told Bild an Sonntag that Peter Raubal, whose father was a nephew of Hitler, 2) would have a strong chance of winning the copyright from Bavaris.
IF the relative tried this (Unlikely possibility), there exists the theoretical certainty of having a strong chance of success..

The other 'coulds' and 'woulds' have similar meanings.