Richard, when starting out, tripod it, and try setting your flash to half power and your aperture to f10 or f11, iso 1-200, and shutterspeed to1/125 to 1/180 and then use something stationary for a test target.
practice shots and histograms will tell you if you need to power up/down the flash.(or move it closer/further from subject)
once you get a good exposure, you'll have a starting point for your learning.

I have nightmares where the last photo I ever take is of a gps guided missile, fired from a Reaper Drone that was tracking me from a chip on my cell phone, coming straight at me. Because I wrote a letter of complaint against a member of Parliment, and got mistakenly tagged as a terrorist.

"I remember the days when my name would have been there... Perhaps I should post more pictures! "

Oversight on our part!

good point on getting "just 'getting enough'" dof. same also goes for flash...some shots look great when you get just the right mix of flash and ambient.

While I'm not known as a macro expert....
I can hold my own when the mood strikes......

While I lack the patience Clarky has for chasing down critters, I do own a 100mm 2.8 macro, and manage some nice ring shots, reflections off droplets on champaine flutes etc in my wedding work.

tripod, ringflash, off camera flash, homemade reflectors/difussers.....

I use my lens primarily for protraits.

you have found the best free resource on the web..so get out there, takes some shots, and keep comming back with your questions.

I got some great dancer shots using the 500 ftz on stroboscopic mode. set the ftz with a fairly slow hurtz rate and had my elinchrom studio strobes also set up (lowest power output settings) with optical slaves.
was able to get upto five or ten images on a frame that way... (anything faster and the studio strobes didn't keep up).

Does it matter?
One only get four or five tries....before one runs out of brands...
after four or five divorces, even the most self righteous will start to wonder... "was it me?"

I use nd grads more than polarizers on my wide angles. easier that way.

hs synch is a good suggestion, but there is another way....
in a darkened room with a darker background, your "shutter speed" is controlled by your flash duration.
therefore setting your flash to it's lowest setting and your aperture (which controls your exposure with flash) wide, and shutter speed can be anywhere from 1/180 down to bulb.
) properly, you'll get "Shutter speeds" well beyond the cameras 1/4000sec top speed.

for example, i use three flashes (one pentax 500ftz, and two vivitar 283's (my viv's have a peice of wire plugged into two of the holes where the auto sensor normally resides, to "short out " the flash to it's lowest setting) to do high speed shots.

great idea....but keep shooting and experimenting.
glowing red embers, hot ash...colored flames, heat waves... those are what I'd expect to see in fire images.

this one is sharp, bright, and detialed, but not very interesting to look at. No sense of "I'm right there in the fire".... know what I mean?

I had the same problem...some sites timed out other not loading at all...
some sites worked fine.
turned out our isp had troubles. when we called them (they didn't bother to tell us...) we had to reset my router with new dns numbers and then everything worked fine.