I recently did a CKD (ran it about a month and 3 weeks or so). I will preface this with I absolutely hated it (although the diet wasn't hard to stick to at all, and I loved my carb up days). I will keep this unbiased, but do say that I think eliminating macros is not the best way to go.
Onto your questions though.
1) Time between your carb ups will be dependent on current bf and goals. Typically iirc, below 10% is a weekly or less carb up, 12-15% could be like 9 days or so, and 15%+ was like 2 weeks. Carb ups will also be determined by how your body responds to ketosis, how long you have to wait to get into ketosis, and overall feeling while in ketosis (non energy feeling should be gone by week 1.5 if done correctly though).
2) Again if I remember correctly from what I read before doing the CKD, glycogen levels went well below 70 mmol/kg bw. I think it was depleted to 70 or so the day after the carb up via cardio, than dropped down to like 40 during the week of lifting and cardio. Either way an individual who has a lesser amount of glyocgen will be negatively effected in the weight room (this is the biggest reason I disliked the CKD). After your body utilizes the CP system for the first few seconds of lifting, your body will release glycogen to be turned into glucose and eventually usable energy. With a CKD your training is dictated by this fact so you can get glycogen stores to a certain mmol level. As far as post workout meals, I love carbs post workout (when I cut I sandwich my carb intake around my training when my body is most sensitive).
3) This again depends on your body type. Some can easily gain despite having carbs near nothing on a daily basis, whiles others, like myself, don't respond that well. Also based on your other questions, CKD has a set up workout program that they recommend, based on glycogen depletion.