The transfer advances (when your RHO passes), start at the level of cue-bid and go up to the simple raise of your parnters suit... so...
(1D)-2C-(P)-?
- 2D (their suit) is transfer to hearts
- 2H is transfer to spades
- 2S is "sound" riase (cue-bid can't be anymore)
- 3C is weak raise
Obviously, if they had opened 1H and your partner had overcalled 2C, then 2D is not a transfer, but shows diamonds. 2H would be spade transfer, 2S would be sound club raise, and 3C weak raise. Works like that.
How to handle interference is still ackward. So only transfer with support with great hand... otherwise use a fit jump (which is more immune to their preemption).
These two hands border on being too strong for a simple 3C raise. With the second one, I would surely use a fit jump to 3
♥. With the first one, I would anguish over what the right bid is. 3
♣ raise is not huge overbid, 2
♦ cue-bid is not a huge underbid, but in final analysis I think 3
♥ is right here too.