I googled this, but couldn't find any answers.

First, am I correct that committing a force die only upgrades the normal power in that it allows you to use dark pips without flipping a destiny point?

Second, can ebb and flow both be activated on the same force check? For example, I roll two pips, can I use one pip to take a strain and give a strain to everyone in engaged range, and use the second pip to recover a strain?

For the first: The Control upgrade basically puts Ebb/Flow on auto-pilot. You indeed don't need to spend Destiny Points to use dark pips anymore, but you don't have a say in whether or not to use them in the first place anymore.

For the second: Since both sides of Ebb/Flow require you to roll them as a Force power check combined with your skill check, you can't do both at the same time. If you're already using your Force dice for an Ebb power check, you have nothing to roll a Flow power check with anymore, and vice versa.

The First:

The commitment doesn't upgrade your base power. It like a power of its own.

You commit one Force dice, and roll your Force from now on with every skillcheck and you HAVE to use all pips generated for sucess or advantage in this check! [not for future checks].

(darkside will still generate strain and conflict for a lightsider, and lightside still brings strain to darksiders. Only you won't need any DPs anymore.)

Since it is now alays a combined forcepower check you also lock away every other force power/ or talent that would require a force check.

17 hours ago, Nightone said:

The First:

The commitment doesn't upgrade your base power. It like a power of its own.

You commit one Force dice, and roll your Force from now on with every skillcheck and you HAVE to use all pips generated for sucess or advantage in this check! [not for future checks].

(darkside will still generate strain and conflict for a lightsider, and lightside still brings strain to darksiders. Only you won't need any DPs anymore.)

Since it is now alays a combined forcepower check you also lock away every other force power/ or talent that would require a force check.

See, this seems like it's worse than the base power. You can already choose to make a combined force check on any skill check with the base power, and choose how you use it. Now that you've committed the die, now you can't use any other combined force checks, you must use all pips, and you can't recover strain any more. The only advantage is not using DPs, but it comes with a bunch of disadvantages. That's what I don't really get.

57 minutes ago, Genuine said:

See, this seems like it's worse than the base power. You can already choose to make a combined force check on any skill check with the base power, and choose how you use it. Now that you've committed the die, now you can't use any other combined force checks, you must use all pips, and you can't recover strain any more. The only advantage is not using DPs, but it comes with a bunch of disadvantages. That's what I don't really get.

The base power allows you to Ebb or Flow as part of a skill check, but you have to decide which before you roll. With all the upgrades, you can spend Flow pips to recover strain, or to give yourself advantages on the next round if you make the same skill check again. If you ebb, you can give enemies strain, disadvantages, or failures on their checks until your next turn. Note that with flow, you have to decide how you are using the pips before you actually roll your next check. So you may take them all as advantages, only to find that doesn't help you.

The Control in question is different. You commit one or more dice as an action. For the rest of the encounter, you have to roll those dice with every skill check, and use every pip. Dark pips cause strain and conflict, but don't require a destiny point flip. You can use those pips as successes or advantages, distributed however you like on that roll. This is better than normal Flow, because you decide how they will be used after you see the results of the skill check.

This is better than, say, Draw Closer in that you can get successes or advantages as needed. It is better than other force powers that do similar things in that it works with any and all checks. It just has a huge cost.