I wonder if anyne has experience with the following (windows xp and higher, i am using 2.6.4. lazarus)
1. As of now, my project allocates all memory on formcreate event and frees on formdestroy. is this good practice or should i be doing alloc/dealloc throughout the app? My memory usage is around 20 megs, so nothing really abnormal and i should be able to shrink that to 15m or so.
20MB? No worries even 200MB in today 6+ GB memory is not going to be a problem, by keeping the memory always allocated you avoid other problems that are harder to diagnose and correct, so if it works don't fix it.
2. I want to let the users to try the app for 30 days. do i need to buy professional tools (for example aspack) to do so or is there any similar free alternative?
Depends is this going to be a one time effort or are you planning to keep "the good fight" for as long as the application leaves? If its a one time think and you do not want to spend time on it or you do not find the concept interesting, then go buy a solution and have people answer your questions. Use an open source solution if you are interested to learn, understand, extend and in general invest portion of your time on the subject then find an open source one and start fiddling.
3. I am storing settings at simple text files. should i be using xml control or is th current system ok? there is only 10 or so settings.
Don't waste time and disk space with xml. Its a attempt for a self contained data exchange format that wend overboard in all accounts. In most case an XML settings files has around 20% data and 80% metadata that describe the data or simple put noise. So no forget about xml for settings if you want a text form editable by any external program then keep your text file otherwise go binary. IT will not help much in your case but its the only sane solution that I would recommend.
4. My app has a fixed form height and width. I realize this might be problematic but I am wondering if it is ok for me to project only for limited number of resolutions. it would make my life quite a bit easier.
My point of view is that its not OK for you enforce your limited capabilities on anyone else other than your self. That said I can't actually recommend anything with out any knowledge about the reasons behind your "limited resolutions" problem. I find it unlikely that in todays GUI and widget set world there is no concept you can use to create a "resolution free" solution. even if that means that you loose something like can't see everything at the same time or resample the results to fit in the screen and loose some details, it is usually preferred than not be able to start the application at all because I do not have the resolution to use it.
5. I will need a website. Any advice of what to use to build it? I will need a forum, some pics, some instructional videos, nothing too complicated.
for easy deployment go the popular way. For fast development go the simple way in general avoid over complicated CMS that will have you jump through hoops to create a simple page because they are "multi language ready" (for example) when you really do not even have a single language up and running. I would go for the simplest solution of all and that is in my opinion wordpress if and when your needs are well documented then choose something more compatible to them.
6. i am using some charts and hence the component tachart. is this ok in closed-source apps? btw: i had problems with labeling the bar charts (there was a limit - only 1 label) so i labelled them manually. is there a way around that limitation? I do not want to breach any copyright, so I will draw my own charts if using tachart for commercial projects is not allowed.
It is part of the official lazarus distribution as far as I know they do not include components that can not be used in commercial applications.
7. I am using text files instead of proper database. Could such approach be problematic in any way? For me it works reasonably fast. But I suppose with some really large files the slow down could be substantial.
"If its not broken do not fix it apply" here.
Now having said that I would really have to know what kind of data are you using how often they change, are you filtering them or using them all to produce your results, and a nubmer of other details that I can't cover in a single post so don't fix it for now.
8. What is the best way to process payments? I do not have a company.
Ask an accountant in your country. Each country has its own rules and regulations if everything else fails contact one of the online money handlers like paypal and try to open an account there they will tell you the minimum requirements to do so.
9. Does anyone have a suggestion about what to use to write user manual?
Avoid html and you will be fine. Manuals should be written in a word processor like openoffice, MS Word, etc or in a more powerful environment like Quark Express better known as desktop publishing applications. If by manual you mean an online help and reference guide then there are a number of good applications out there like help & manual, do a search for help authoring and you will get a number of applications that can create pdf, web sites, and online help files from a single source.
10. My app has no menus, generally I detest menus and want to have visual control over all settings. is this generally ok? I am also using a lot of colors? I should probably not overusing it, right?
No. Especially when you force a resolution limit on me. At this time I would say use a menu then we can talk about resolution requirements.
I realize I am asking a lot of questions, so I will be glad for any answer to any question. The most important thing is avoiding doing something really stupid. 
As you can see I avoided answering a number of questions. I do not have enough information to begin making assumptions.
Recent
