Update! I have had a TON of requests for this. I have created a bundle of all of my brushes in one set! I have them hosted on a new website www.vfxmill.net for bandwidth reasons. I will be posting a new set in the next few days! Please stay tuned and check out the new site in the meantime :)
As always I will post updates and new brushes on my portfolio site. www.michaeldunnam.com. Once you click on the new brushes you will be redirected to vfxmill. Enjoy! 
go to vfxmill
go to my portfolio site
As always!Enjoy!
-Michael

Ok so here is what I know. Apparently Z4R3 is compatible with 2048px alphas. Which a lot of the brushes are using. 
So far this has worked 100% of the time from what people have told me. Upgrade to R3, if that doesn't work. Uninstall and upgrade again. 
Another issue. The lag issue. I might at some point... Downres all of the alphas to 512 so they are backwards compat with all versions of Zbrush back to 3. This will take a lot of time to do, b/c I have to downsample each alpha, reimport and resave each brush. Then reupload to the site and repackage etc etc. I have tested it and I believe it fixes the lag issue as well as the back-compat issue.
If I do this I will package all of my alphas in 2048 to give away in a separate package.
I am going to do some more testing before I go through all of this trouble. So if anyone else could test upgrading to R3 if you are having alpha issues and post. This would help me very much. Remember I am doing this for the good of the community. I expect nothing in return. So a little help would go a long way :)
Thanks!
-Michael

Update! I have packaged each Brush individually with the highest resolution alpha that was made to create the brush as well as the icon. Just click on the icons and download the brushes again if you want them individual. Each one is RAR'd. The Packages have also been updated to include all of these RARs. This took a ton of time. So please be kind and enjoy! :) 
I will eventually include an alpha only package for those that just want the alphas!
I will create some new brushes soon!
As always, Enjoy!
www.michaeldunnam.com/free-stuff.html
Michael

I created a small set just for fun. 



Let me know what you think. Some of the settings for the fabric might need to be played with a little to get the desired results. They work fairly well with a wacom. I used a few pen pressure settings. Adjust what ya need :)

As always!Enjoy!
-Michael

New Set of Brushes are now available! I have created some long awaited Mech Insert Brushes! Sorry these took quite a while to create. I am still in the process of making the stitch brushes. I just ran into a snag along the way. Stop on by and grab these new brushes. They work fantastic as additive or subtractive brushes. I hope everyone enjoys these new brushes. Leave some feedback on my blog or one of the forums posted! :) And please follow me on twitter or my blog so you know when I post new brushes.





Enjoy!

-Michael

Sorry for the delay. I am currently working on a complimentary set for the Mech Brushes! Coming soon! :)

Here is my new set. Sorry alphas only this time. I had problems getting the stitches to work like the zipper brushes. If anyone would like to give it a try and send them back if you get them working correctly, that would be awesome. I would give full credit of course!


www.michaeldunnam.com/free-stuff.html


Hope everyone enjoys!
-Michael

Now available! My first set of Premium brushes. Do not fear though, not all brushes are going to cost you from now on. These brushes took a long time to make and are well worth the $2.00. More free brushes coming soon! I am now working on another set to follow these that will be free! Enjoy!


http://www.michaeldunnam.com/free-stuff.html#MechInsertSet2


Enjoy!
-Michael

Here is a small set of screwheads I was just playing around with. They are hosted at www.VFXMill.net. And will be from now on. Take a look! I hope you enjoy.




http://www.vfxmill.net/vfxmill_freestuff.html

-Michael