Example:
i have X ICP and place them into a Neuron for 365days and get a voting power of Y.
A.) In order to get back my ICP currently locked for 365d, when do i need to start disolving my neuron? after the 365d have passed? Also, if so, do i get them immediately, or is there another delay i need to think of?
B.) Voting: when can i vote? Is it immediately after locking ICP into a neuron or after the delay (365d)?
You have to start dissolving 365 days before you want to get them out
Immediately for any proposal that is created after locking. In practice this roughly means that after 4 days you can vote on every proposal that is open
To simplify even more you need a minimum 6 months lock to be able to vote. As @Severin very accurately described you can vote from day one if the min 6 mo is in place and starting on proposals created after you did the staking. One thing to consider is that when you reach the last 6 months remaining to dissolve you can no longer cast a vote, so take that into your calculations. So in your example for one year if you start after 6 months you will get rewards for voting for 1 year but will be able to withdraw after 1 and a half year.
Sorry, more questions:
Is it then “usual” to lock them in a neuron for X days and immediately after start dissolving?
The longer a neuron remains in a non-dissolving state, the more the bonus increases. So some people keep the neuron locked to receive a larger bonus.