[Campion]

Is it safe to assume all major teachings, ordinances, practices, etc., are from infallible teachings? Is the Catechism an infallible teaching?

No. Practices are never infallible. The Catechism itself is not infallible (though it asserts truths which have previously been taught infallibly).

What passages in Scripture do you think are contradicted by the Catechism passages you cite?

[FactQuest]

“Being justified freely by His grace through the redemption that is in Christ Jesus.” Romans 3:24

“For by grace are ye saved through faith; and that not of yourselves: It is the gift of God: Not of works, lest any man should boast.” Ephesians 2:8, 9

“For if by one man’s offence death reigned by one; much more they which receive abundance of grace and of the gift of righteousness shall reign in life by one, Jesus Christ.” Rom 5:17

“Not by works of righteousness which we have done, but according to his mercy he saved us...” Titus 3:5-6

“I do not frustrate the grace of God: for if righteousness come by the law, then Christ is dead in vain.” Galatians 2:21

Or, to put in into the terms of the Reformation, sola gratia. Not by ordinances, not by works of righteousness.

Please don't get me wrong, I'm not one of those crazed evangelicals that thinks the Pope is the Antichrist or that all Roman Catholics are going to hell. I don't. I think God has used the RCC in a mighty way, preserving the Christian faith through the centuries. I don't, however, think they, or any other denomination, has perfect wisdom, or perfect teaching. And I think God is big enough to use us, his imperfect vessels and the imperfect Church (meaning all true believers, Roman Catholic and otherwise).