The Texicans, who were actually invited to settle in what is now the state of Texas by the Mexican government, did indeed write and enact a Constitution in 1836. The fact that they didn't produce an exact photocopy of the Declaration of Independence is simply a red herring on your part.
Indeed, the Mexican government promised prospective settlers that they could "continue to enjoy that constitutional liberty and republican government to which they had been habituated in the land of their birth, the United States of America." However, upon overthrowing his own government, Santa Anna broke that and other promises. Among other outrages, Santa Anna imprisoned Texicans in an attempt to blackmail the others into accepting his edicts, conducted military drumhead trials of settlers on trumped-up charges, conducted punitive military operations (including piracy) against the settlers, and failed to ensure even the most basic human rights of the settlers.
Or didn't you read my post carefully enough?
I was desperately trying to figure out what point you were trying to make in your post. When trying to make a point, most people do so as early as they can in a specific article or speech. Here are the first two sentences of your previous post:
The hicks in the nacent Texan Republic were on Mexican soil. They refused to accept Mexican authority and started the war in 1835.
Sure looks to me like the main point you were making was that the mean ol' Texicans somehow done the government of Mexico wrong. Well, I've got news for you - people living under the thumb of a tyrant tend to do that, just like the denizens of the 13 Colonies did.
And, as for the slavery issue goes, I'd be interested in reading your explanation of just how the Texicans "adored" slavery? Last time I cracked a history book, about half of the United States at the time didn't have clean hands on the same issue. There was this little dustup called "The Civil War" that happened later - you might have heard of it?