Ok, first of all you'll want to know that we do not promote/support CIO in any form on this site. Granted, there are some moms on this site that have tried it and it has worked for them (I'm one of them, admittedly-although I've used a combo and now exclusively use the BW method when my lo wakes too early from naps and has trouble going to sleep) with no problems. However, all methods used on this site revolve around an attachment style of parenting, and many moms here are very strong supporters of non-CIO methods.
That said, let's work on your day
First of all, you'll want to develop some kind of routine. Most babies seem to thrive on that...they like to know what comes next. If you haven't already, create a nap-time routine (it doesn't have to be involved) and a bedtime routine (this one can be involved). Give yourself at least 15 mins before naps to wind down.
It looks like your bedtime is actually between 6:30 and 7 pm. You'll probably want to start bathtime around 6, and have the routine completed between then. The reason he slept for 4 hours at once is because he was starting his nightime sleep pattern...of this I'm pretty certain.
Nursing wise, to follow EASY, you'll want to have him eating every 3 hours. He's old enough that he should be able to wait that long...maybe a little longer. Because of the short napping, he may be following the routine of EASAEAS. This is perfectly fine, the EASY plan is pretty flexible.
It looks like you have him up for about an hour before putting him down. Now may be the time to extend waking time to closer to 1.5 hours (maybe an hour and 15 or 20). Do it in 15 min incraments...it may take a week or so.
As for the CIO issue...first of all, what you need to figure out is what is him actually "crying out" to you, and him having fussiness and mantra cries in order to get to sleep. With crying out the tone of his volume and pitch tends to raise, and it sounds more like an "I need you NOW!" cry. A mantra cry is more of a steady whaaa...whaaa....whaaa... sound, and doesn't raise in volume or pitch. Sometimes there's coughing. We don't go in during the mantra cry, but we do get in there immediately if it sounds frantic. Babies usually take a full 20 mins to settle and go to sleep.
Let's make a typical plan up and work toward it.
W/E: 7 am
A: 7-8:00
S: 8:00-9:30 or 10
E: 10:00
A: 9:30-10:45
S: 10:45-12:15 or 12:45
E: 1
A: 12:45-2
S (catnap) 2-3
E: 3
A: 3-4:15
S: (maybe another catnap) 4:15-5
E: Cluster at 5:00
A: 5-6
Bedtime routine at 6 (including a feeding)
Bed between 6:30 and 7
Dreamfeed at 10:30-11.
Maybe 1 extra feeding sometime during the night if necessary, soothing back to sleep every other time using WTS, pat/shh and/or PU/PD.
Now this is ultimately what the "perfect" plan might look like for your lo...but by no means should you expect to get it right away or expect it to eventually fall into that sort of schedule perfectly! Sleep training can take a good week. The idea is to be flexible and above all consistant...if your lo wakes after 45 mins, 1 hour and 15 mins later (or however long he needs to be awake) put him down for his next nap. Do low-key, soothing activities, and make his wind down extra soothing. You're starting into a period where day sleep is developing...lots of 45 min naps are normal until it works itself out. Watch sleepy signs, not the clock, but use the clock as a guide. If you put him to bed too early, you'll get 40 min naps. Too late, and you'll get the same, as I'm sure you know. Play with it...you know he needs to be up a little more than an hour right now (probably). Also, don't get too upset if he takes short naps...he can sense your anger and frustration, and it will make things worse, trust me. They are amazingly sensitive little things!
BTW...I put my lo down on her tummy as well. It does seem to help her sleep better, but I'd rather she be sleeping on her side.
Hope you can find something in this that helps!!
*HUGS*
Sonya =P