I tried this template earlier this summer, albeit with quite low carbohydrate and couldn't gain any weight, despite a 1000+ calorie excess and almost no "met-con" work. I chock it up to 2 problems: 1) like mentioned here, you need to add way more carbs than 'seem' right on paleo, and 2) 531 simply didn't feel like enough volume.
That said, I felt awesome, and was certainly getting stronger, I just wasn't putting on weight.
I ended up adding in more sweet potatoes, rice, and fruit, doing the weekday programming of CFFB (amateur SWOD and off-season DWOD), and starting up half-GOMAD (on workout days) and the weight gain commenced.
Two things to keep in mind: Paleo (especially low-carb) does an amazing job of managing insulin levels. Insulin is a very anabolic hormone.
The other thing worth note is what Robb said in one of his podcasts with reference to mass-gain cycles. It is probably worth your time and money to seek out a good naturopath and make sure your baseline is good with respect to hormone/mineral levels and systemic inflammation. You could, in theory, eat a 2k calorie excess, but if your cortisol levels are high and test levels low, just gain fat. If you start all of this with everything functioning as well as possible, you'll get the most bang for your buck on food bills. And let me tell you, with that kind of calorie intake on Paleo, they add up quick.