I've remodelled the Guestbook app from scratch and deployed on both emulator and a Samsung Galaxy, but see no significant lag.Since I'm using a newer version then you (the very latest code we have), that might explain the disparity, however I'd be very happy to test your project in my version if you post it here, with detailed instructions on how to recreate the problem (or if you'd rather, you can send it directly to us).
The error message you quoted previously, despite your client-side configuration, is a server-side message. It seems you have some process modeled directly in the root system (outside the <Mobile View> or any other view). Such processes will always run on the server when the application is started, and if they fail the application fails to start. BTW when you export such a project to native, the said processes do not get exported at all.Support for non-ascii characters (and other special characters such as space) in database schema definitions has been implemented just recently (using quoted identifiers) and will be available in the next version.Again, you're welcome to post/send the project for us to test
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