Actions' Weighting Values will not Save

7.x-2.0+15-dev (2012-Jan-25) (but same problem with 7.x-2.0)
D 7.10
(Rules Bonus Pack,
Rules Forms Support)

I have two Rulesets (originally cloned from each other) one triggered on content save the other triggered on content update.
They each have 17 actions (mixture of Setting Data, Fetching Entity, Scheduled Component etc).
When I rearrange the weighting of these actions by dragging and Saving they remain where I put them. However, they seem to be listed with the top Action given a weighting of zero and yet the bottom 5 are given equal weighting of -20! This in itself seems odd but I need to differentiate these 5 Actions to ensure they are executed in a specific order as they do not appear to be at the moment.
I have disabled Java and used the dropdowns to assign specific weights to each action but, on Saving these weights are ignored and the previous weightings assigned (again listing from zero down to the bottom group having weights of -20!
With Java enabled, if I simply press Save (without dragging anything anywhere) again the Actions are rearranged in what looks like a random order. If I press Save again the Actions are again rearranged.
I tried to find the weightings as recorded in the DB under dr_rules_config but only one of the Rulesets appears there and there doesnt seem to be any reference to the Actions at all so I guess I must be looking in the wrong place.
Sorry if I am doing something stupid but I've been through the issue list and cant find anything similar. I'm baffled.