Hi Michael and welcome to the forum. I’ve done a little digging into your questions and here is what I found.
Free trial versions of STEP 7 V5.6 download Customers using STEP 7 V5.3,. Download simatic manager s7 for free. Development Tools downloads - SIMATIC S7-PLCSIM + SP4 Professional by Siemens AG and many more programs are available for instant and free download.
This is a bit of a hack so try at your own risk: To install STEP 7 v5.5 SP3 (DVD update release) follow these steps. Download and install the latest 64-bit version of automation license manager. Copy DVD content to any directory on hdd. Modify./Setup.exe using any resouce modification software.
Eg ResourceHacker. Add the line //this is the os ID of Windows 8 64bit 4. Modify./InstData/Setup.ini under section OS. PlattformIDAllowed = 1;2;3 Add the lines Win8x64=1 Win8x64Exclude=SKU2;SKU3;SKU5;SKU8;SKU9;SKU10;SKU11;SKU12;SKU13;SKU14;SKU15;SKU16;SKU17;SKU18;SKU19;SKU20;SKU21;SKU22;SKU23;SKU24;SKU25;SKU47;SKU66;SKU67;SKU68 Win8x64Warning=SKU2;SKU3;SKU5;SKU8;SKU9;SKU10;SKU12;SKU13;SKU14;SKU15;SKU16;SKU17;SKU18;SKU19;SKU20;SKU21;SKU22;SKU23;SKU24;SKU25;SKU67;SKU68 5. Modify all msi-files to enable the ingore-button on installation failures (like installing on unsupported OS’s). Use any software possible to manipulate MSI-files.
Search for DLGINSTALLATIONREQUIREMENTSDISABLEIGNORE. Change Action from Disbale to Enable. Run./Setup to start installation. Press the ingore-button when told it’s not possible to install on running OS. Good luck and if you’re looking for an excellent text on this and Siemens programming – check out this book on Amazon, I highly recommend, it is excellent! Check out my article, it may surprise you.