Paul, it does look like you over-turned a bit. It is useful to turn a blank just proud of the bushings. Not by much, just a smidge. You would then sand, which will take off more material (particuarly at the lower grits). You would want to sand down to just the point where the blank ends are as large in diameter as the bushings (try not to sand the bushings though, as that will reduce the bushing diameters over the long term.)
When you try to turn down to the bushings exactly using just the tool, its easy to go too far, and there isn't much that can recover from that (CA could be built up, but CA looks and finishes differently from alumilite itself, or most other resins except maybe acrylic).
The blank does not look bent to me, but it does appear to have some peaks and valleys. That is just a matter of practice with your tool, and eventual skill, so keep at it! I am curious, what kind of tool did you use? Some tools work much better with resins than others. Gouges are probably not the best. Easy Wood Tools with negative rake tips are good. A skew might be good, but is usually a much greater challenge, so I'd only use a skew if you have enough skill from turning wood with a skew. A gouge, in my experience, will very easily shred resin blanks and cause a lot of chipout.
