1. At any time during a "Bulk" diet should one LOSE any weight? Should one fluctuate to a weight which is LESS that the week before?
No matter what you can see your weight fluctuate on a scale. Make sure when you weigh in that your doing it at the same time of the day, after the same amount of meals. If you weight yourself monday morning at 200 pounds, and the next monday you weigh yourself at night at 210, that extra weight is coming from food and water.
2. How long does one typically stay on a bulking phase? I've been on one for the last 8 weeks and only gained 5 pounds. Probably all fat and water.
What is the typical weight gain target amount while on a bulk phase?
Length of a bulk or cut pretty much depends on your goals. If you want to gain 10 pounds, bulk until you gain 10 pounds ya know? Everyone is different, some people can gain more muscle quicker than others, but a pretty safe bet is to aim for 1 or 2 pounds per week. That means that you need a caloric surplus of 3500, or 7000 calories per week.
3. Does cardio have it's place during a bulk? Doesn't seem to make sense. If I'm eating to gain, why would I spend the excess calories on cardio? Raising my metabolism during a bulk seems counter-productive to me.
Overall health yes, the cardiovascular benefit is nice and to keep good health, but if your strictly trying to gain mass, than I PERSONALLY wouldn't. A lot of people do a little cardio during their bulk though.
4. What macro percentages are best for a bulking phase? I'm currently doing 45%c, 30%p and 25%f. Should I be doing 45%p, 30%c and 25%f during the bulking phase or should I save the latter macro numbers for the cutting phase?
Again, everyone has their own ideas on this. I don't follow specific macros, I just balance it out as I eat each meal and am in my last month of a very successful bulk. It also depends on what time your eating the meal. After workouts you can really load up on carbs, a lot of people recommend 70 to 100gs, but I personally wouldn't eat 100 grams any other time of the day at once. Many Recommend a 40P 40C 20F, but if you want to plan it out the best rule of thumb is 1 or 1.5 grams of protein per pound of bodyweight, and .5 or a little more grams of good fats per pound of bodyweight. Fill the rest of your calories with good carbs.
5. As mentioned, this past week I reduced my diet from 4500 down to 3600 and I lost half a pound. Should I be concerned about this? Should I give it more time before adjusting the numbers?
Use this to calculate your BMR -
BMR Calculator
Then use this to calculate your daily maintenance needs -
Harris Benedict Equation
Then use Fitday.com to create a good diet plan, it will tell you all the calories and macros, as well as vitamins and minerals.
Eat 500 calories more than your maintenance to bulk, or 500 less to cut. After a couple weeks, make small adjustments if you need to.
Good luck brotha!