You get credits based on how many nights you stay at the resort. You cannot get more credits or fewer credits than that. The only way to add credits is to add nights on to your resort stay. Or you can upgrade to the deluxe plan which includes 3 meal credits per night you stay instead of just 1 TS and 1 QS credit per night.
If you stay 7 nights on the regular plan you get 7 TS credits per person. Then you have to decide where and when to use them. If you use 2 per person for CRT then you will have 5 left for the rest of your stay. If you wanted 7 TS meals, you would then have to pay for an extra meal. If you were staying 7 nights and 8 days and you wanted 8 TS meals, one for each day, then you'd have to pay for 2 additional meals. or just pay out of pocket for CRT.