Write installer for a .NET application

Hello, We need an installer for installing a .NET application on Windows machines. The installer can be written in NSIS, or using a different software / scripting language, pending our assessment and confirmation (prior to the acceptance of the bid - so please indicate in the bid how you plan to develop the installer). 1. The installer is pretty standard: 1.1. Check if the machine has .NET 4.5 installed. Download it from Microsoft and install it automatically if it doesn't. 1.2. Install our software, which consists of executable files and DLLs. 1.3. SILENTLY install CSSN's SDK (version 10.01.29; can be downloaded here: [login to view URL]) (this SDK should be part of the installation package, not downloaded as part of the installation process). 2. There should be a wizard with the following steps: 2.1. Welcome screen with our Logo and some text. 2.2. T&C approval screen (make it required to proceed with the installation). 2.3. Installation directory selection screen + disk space check. 2.4. Checkboxes selection of where to put shortcuts (start menu, desktop, or both; both checked by default). 2.5. Actual installation. 2.6. Thank you screen + a checkbox allowing the user to start the application immediately. 3. Along with the SDK and our software, an uninstaller should be installed as well. 4. If attempting to install on a machine where the software is already installed: 4.1. The user should be prompted to select whether he wants to update (he/she will NOT be forced to manually uninstall first). 4.2. If the software is running, the installer will prompt the user to close it and will offer a "try again" button (which will re-run the check, and proceed if the software has indeed closed). 5. In addition: 5.1. The installer should configure our software to require running in elevated permissions mode (force "Run as Administrator"). 5.2. There should be a version string that would be easy to change in the script when preparing a new install, and will appear in the welcome screen of the installation wizard. 5.3. The full code and all related assets of the installer will be provided to us, and we will be the sole owners of their copyrights. 5.4. The code is to be written in an efficient, clear, and abundantly documented manner. 5.5. Full instructions and examples for how to manage and compile the installer are to be provided. 5.6. Instructions, scripts, and a working example for signing the installer with a certificate will be provided (using a demo certificate the bidder will find or generate). Please indicate the technology you'd like to use, and provide a delivery timeline along with your bid. Thank you!