"Was Spain the first country to pull troops out of Iraq ?"
I think that was the Philippines, but I may be wrong.
"We all know that the country suffered a very conveniently timed terrorist train attack on the eve of an election that was utilized by the Socialist to take over the Spanish government."
The Spanish Conservative government tried to use the terror attack to blame it on the Basque separatists and tarnish its political opponents which included Basque autonomists, and that plan backfired big time. Plus, while the Spanish government did send troops in Iraq as part of the Coalition, a very large majority of Spaniards were opposed to it.
No need to add any conspiracy here : you have a government conducting a policy the population is largely opposed to in an election year, and who embarasses itself trying to use a terror attack to divide the country instead of brininging it together as the US did after 9/11. Predictably, the electorate gives the boot to said government.
"Was Spain given complete plans for the US forces ?"
Not sure about that. After all, the Spanish contribution was only 1,200 men strong, which meant the Spanish deployment area would be modest. And I don't think they were directly involved in the assault against Iraqi forces. Why then would they have been given the whole operational plans instead of just what they needed to deploy ?