Electrical issue...maybe?

[clayton]

Sorry for double posting since I placed it in the More Questions thread I started awhile back but I feel that might be dead...
Anyway...
Since I am no electrician I will be a specific as possible.
Awhile back I did the wiring from info on Gadgets site...
The setup is as follows...
30amp relay...wired directly from battery
3 slot fuse block running off of the relay
On the 15amp fuse I ran some running lights...cheapy's from Wally World...
In turn I also tapped into the line adding an accessory outlet prior to the switch that controls the lights so that when the engine is on so is the accessory outlet.
The issue is when I plug in a GPS, the fuse in the GPS's charging cable blows...even when the engine is off and only the ignition is turned on.
So I pulled out the multimeter and here is what I have...
With the ignition on and the light switch off I get 12.5 volts
With the engine running I get 14.6 volts...
Now then here is the weird thing...as soon as I turn on the driving lights the accessory outlets current drops to some where around .025...
Now I moved to the fuse block itself...
With the engine off and the ignition switch off I read about .005 volts.
With the ignition switch on (no running engine) I read about 12.5
With the engine running I read 14.6 across all fuses.
So....what should I do?
Single out the lights from the accessory outlet? Maybe some back feed?
Might I have a bad relay or fuse block?
Any help would be great.
I also messenged Mac on this to get his input.
Thanks all

Also I have something to ask...so don't laugh
Could I have the polarity backwards on the accessory outlet?
I know in AC it does not matter so much but what about DC?