And what about the middle mouse button that closes the tabs? It's not a real shortcut, but it's really useful and time-saving. It also works with the Chrome and Edge tabs.

I suggest OnShape, a fantastic completely web based cad. There is the free version which, as the only limitation, makes all your documents public. It is really well done, it is parametric and it has a lot of professional features. It also allows you to import STL files (I've never done that), but I don't think it has any specific cleaning functions.

I suggest you LG G2: good screen 5.2 inch (full HD), and good camera (13 megapixel) Or LG G3, but it's expensive and the screen size is big: 5.5 inch (2560 x 1440 QHD)

"Catastrophic error" is a real message I've seen years ago, from Windows XP.

If you are interested to DirectSound, look at SlimDX. From the official site: "SlimDX is a free open source framework that enables developers to easily build DirectX applications using .NET technologies such as C#, VB.NET, and !IronPython. It is designed to be an efficient, simple, and lean wrapper that fully encompasses all of Microsoft's gaming and multimedia technologies and exposes them to managed code. " I use SlimDX not for audio but for 3D application and I think it is very well done.

I use iTextSharp to add logos or to merge different pdfs. It works well and fast. For the pdf viewer (in Windows Form) I use the standard WebBrowser control, but the Adobe Plugin must be installed, and I search something better. I'm investigating on a PDF rasterizer like: http://www.tallcomponents.com/products.aspx http://www.softwaresigloxxi.com/SuperPdf2ImageConverter.html Exists also an article in CodeProject: PDF Viewer Control Without Acrobat Reader Installed but it has a lot of dependencies.