Acrow prop, how to use? and advice please

Hi, obviously I am starting this thread in search of assistance on how to use an acrow prop.
I know that they are an adjustable metal post used for holding heavy things up while things are done, eg renovation replacement etc.

I do own two acrows (which have finally been returned to me after a lengthy period down the coast :(( :~ ) It looks like they could be rusted up, but as I dont know what bits are supossed to move and do what, I am not sure what bits to try and loosen up.

Ok, the advice bit. Assuming that I can get an acrow to work (when some nice person hopefully tells me how :) ) what I need the acrow for is to hold up the back porch while I repair the post (which is the only bit of timber left holding anything)
What I was thinking of doing was, while the post is being held up, cutting off the bottom 6", and putting one of those long post brackets on the bottom. To secure the bottom, I was giong to skew drill some holes back into the stone, concrete some bolts in there to tie it in together, and build concrete out around the corner of the porch to support it.
I was thinking, instead of using concrete boxing, I would get some bricks, and build a little wall around it, wait for that to set, then just fill that with concrete.

Most of the post is still solid, it is just at the bottom that it is rotted out. It is some type of hardwood, although I wouldnt know what sort.

once you get the acroiw prop, i think it will be self explanatory how to use it - though a tip is to always secure the top with nails through the plate holes, and if it is against a painted surface then the prop is nailed to a piece of 4*2 so the weight is spread wider than just the plate of the acrow prop - BTW clockwise is to to tighten (ie lengthen) - if its anti clockwise you have it upside down ;)

that post looks suspiciously like its bolted to the wall to me and that is where the weight bearing is - regardless, you might be better advised to make the existing concrete base flat and stable (ie remove cracked and broken concrete), and either ramset concrete anchor or chemset in 2 bolts to hold it down - using the post brackets that have a base plate and 2 holes for securing. Tie down is equally important to weight bearing so both must be considered.

Thankyou pharmaboy2.

Further pictures added for clarification. (the pics took ages, dialup sux)

I have had another look at the acrow prop. It has been let sieze up, and has filled with sand. I have got it moving enough to work out what bits I need to get unseized so that I can use it :((. Guess who I will not be lending anything else to again.

Ok, the bottom of the post, here looks like it has two bolts running from it into the concrete.
The "T blade post stirrup" from here was something like I was thinking of using, except the one that I want to use has a "U" at the top for the post to be bolted into. I was thinking if I just concrete the bottom half of this bracket into the concrete when I do it, that should hold it pretty well, as long as the concrete p[atch is tied back into the existing concrete pretty well.
Ok, a pic of the back verandah, (yes, is is now pretty bad, has slowly been degrading for many more years than I can remember) The timber uprights between the louvre windows have rotted out, and are basically holding nothing.
I have recently noticed that between the post and stonework a gap is appearing that hasnt been there before, and the concrete corner has finally cracked off.

Now, regarding the acrow prop, do I just use that to lift up the beam that the post is attatched to, I assume that I will need some diagonal bracing to stop any potential sideways movement of the verandah.
How long after the concrete is poured would I need to leave the weight off for, eg, leave the acrow prop set up?

Nice tip for siezed up metal parts- spray them or if possible soak them in Diesel fuel for a day- then coat with blue grease. works a treat.