Siebe said: “2. kamma-vipaka refers to what happens as a result or consequence of an intentional act. So, when i decide to take a shower, the nice feelings of the warm water are kamma-vipaka because they are a result of my decision to take a shower. The feelings do not arise from a good-kamma beeja, but they arise as a result of contact with nice warm water.”
Yes. It is a kamma vipaka (result of an action). Taking a warm shower leads to a nice feeling.
It is not necessary to connect all kamma to kamma beeja that last into future lives. Some actions have results right away, or during the current lifetime (called dittadhamma vedaniya kamma). For these, one could say the kamma beeja uses its power right away or at least by the end of the lifetime. Long lasting kamma beeja are there for other types of stronger kamma where results can appear in future lives.