Complaint Review: Smith Consulting

I contact David Smith of Smith Consulting in early 2010 regarding customization of his existing ecommerce software SmithCart, for a client job.
He informed me he could provide the services for the cost of the cart plus a favour.
I performed the favour, and created a header slideshow for his site that would show SmithCart and several other Smith Consulting products.
I also paid him the sum he requested which was $250 usd.  Effectively I purchased the cart, paid him fifty dollars and created him a slide show header.

The customization was the addition of a feature that would acquire shipping quotes from Canada Post.  There were existing solutions I could utilize, but they required multiple softwares and would not be as efficient (so I believed).

The feature was written and I installed the Smith Consulting's SmithCart which worked alright, save for the extra features he had written.

After some email correspondence it became clear what the issue was and I was forced to rebuild the site to allow the feature to work correctly.  This was not Mr. Smith's fault, but a limitation in the hosting I was initially using.

After the site was rebuilt upon a new host, the software functioned, and it seemed all was well.

Fast forward a few months and my clients business has slowed, online orders seem to have faded and there's no explanations for a large number of exceptions and errors being caught by the websites logs.  Emails regarding these errors are never responded to and I'm forced to examine the issues.
In short, if there was any issue with the information provided by the customer, SmithCart would simply provide an ugly 'Critical Error' page and cease to function until the 'session' was closed (which may take up to twenty minutes).  This is really bad because basically it means customers are unable to complete their order and upon reviewing the Google analytics, my fears therein were confirmed.  People were simply getting turned away by Critical Errors that would appear for the most minor of glitches, such as mis-entered postal codes, or incorrectly selected country/state/province, etc.

During this time, Dave requires some graphics made.  Nothing extravagant, but it is something I provide, and then provide adjustments, and then a final product upon.
You can see my work at http://xceliware.com

I bill him for my work but my bill goes unpaid, and the issues go unresolved until suddenly an order goes through but no shipping is added to the order!  At this point obviously something is very wrong with SmithCart.

After repeat emails to David Smith of Smith Consulting, I receive an updated version of the SmithCart software in a link.
My client requests I hold off on the installation of this update, but when another order suddenly goes through, this time very large, with no shipping fees attached, they ask me to spring into action, but when I revisit the issue, the links David Smith provided to the latest SmithCart, have expired.  Why?  No reason, just because.

The problem with the SmithCart is simply this:  A customer can simply continue to checkout without adding shipping to their order.  The feature is outright broken!

I request a new link be provided so I can install the new version to correct the issue and he requests that I explain what the issue is (even though he has email records of all the issues SmithCart has reported to date).  I patiently explain the issue to which he responds with a link.
I install the new software and the problem persists!  Many other aspects of the cart were obviously improved and fixed but this one feature was still broken.
So I make him aware of this, and he dutifully provides a test site where I can confirm if the issue is rectified.
It is, and I request a link, stating that he still hasn't paid my bill.
He claims that I owe him money for the updated cart and refuses to pay my bill.

Given he owes me a paltry $150.00 and lives in a different country, I have no choice but to take it in the a*s.  I need the WORKING software to complete the job.
However, I've decided to publish this little report so people can see why I'm upset.

In short:  I paid him for a feature which he provided broken.  This broken software and feature has cost my client a lot of money and business.  This broken software is still costing me time and effort.

To top it all off, this a*****e decides to withhold a hundred fifty dollars so he can feel justified in providing me a fix to his broken software.

Yes Dave.  You are an a**hole.
I'm still reconfiguring SmithCart, and nobody is covering that expense, you d**chebag.