Updated to .99i this morning and suddenly my database is corrupt!
Was able to get your database file from the link you sent and reproduce the issue. I'm replying here in case others are experiencing something similar.
The problem is where I thought it was, it's running into an error in the schema upgrade process. Specifically, it's trying to migrate the contents of the "chatchannel" table to a new table with different columns, and getting a constraint violation inserting it into the new table. From looking at your database, I see that several of the tables are referring to character IDs that don't exist in the character table.
That's a situation that should be impossible, since Paragon Chat always runs with foreign key checking turned on, and only deletes characters after removing all of the associated entries from other tables (it would get a constraint violation trying to delete the character otherwise). It also does all of that inside a transaction, which SQlite guarantees will not be written to disk in a partial state if something goes wrong.
Have you been editing the database manually? That's the only thing I can think of that could cause that situation. Foreign key checking is not turned on by default by the library, so using a third-party sqlite editor tool would ignore the data integrity constraints if you don't explicitly turn it on.
If you have been editing the db, are comfortable enough with SQL, and don't mind losing your color settings for global channels, a quick fix would be to delete all the rows from the "chatchannel" table (but don't delete the table itself!).
Alternatively, you could delete just the rows from chatchannel that reference nonexistent characters. In your particular database, these would be the rows where the character column is 19, 20, 21, 27, 29, 30, 32, 33, 38, 41, 42, or 44.
Once you do that, the schema migration will be able to succeed. You'll still have some inconsistent data in there that may bite you in the future, but it should be okay for now.
I'll look into adding some kind of database repair option in future versions of Paragon Chat to look for and correct these kinds of inconsistencies. I hadn't done it so far because sqlite's constraints and its ACID transactions are a bulletproof way to make sure they don't happen to begin with.