underdone

Honestly, don't bother with Script Hook V. If you want to do anything LSPDFR or police related, stick to Rage Plugin Hook.
There is a bit of a learning curve, but once you get the hang of it, things get easier.
As FtDLulz said, download Visual Studio Community 2013. Its free, and it is "straight from the horse's mouth", so to speak. Its a Microsoft tool, and Microsoft makes the .NET Framework, which is what all these plugins are developed on. The Community edition does not have all the tools that the professionals use in the Premium and Ultimate versions, but honestly, it doesn't matter. Community has more than enough built into it...take it from someone who is a .NET Developer for a living. I make money and pay my bills doing this stuff, and I use Visual Studio Premium at work. I find that Community is more than enough for stuff I want to do with LSPDFR scripts.
Now, all that said...DON'T LOOK AT ANY RAGE/LSPDFR CODE YET!!
Don't do it! I know you're looking at LukeD's Example API project in the other thread...its tempting, isn't it?
Well, don't download it! I'm watching you...
Okay, seriously...I would strongly suggest looking up some tutorials online on how to code in C#. Learn about the basic concepts...learn what a function is, what a variable is, what a loop is, etc. Start by making a program in C# that opens a Command Prompt (DOS) window and writes "Hello World!". You can do that one in about 5 minutes...literally.
Hint:
Console.WriteLine("Hello World!"); Once you're done that, and you're comfortable using Visual Studio, then follow the Rage Plugin Hook Getting Started guide in the Rage Documentation. And you'll be off and running! 
At that point, download LukeD's example API project from this subforum. If you take even just one or two days to learn some basic C# concepts, then you'll be far better off, and you'll be able to read and actually understand the example code that Luke has written. (Keep in mind that Luke's example is for developing an LSPDFR callout plugin...the guide in the Rage Documentation is for developing a script mod for GTA V...two different things!)
Feel free to post in this forum if you need help.
Good luck!

Following on from the massive debut of LSPDFR on GTA V a mere two weeks ago, we're proud to announce the next installment in the series - LSPDFR 0.2 - featuring not only numerous enhancements and fixes, but also some highly requested features.
Indeed, while originally versioned as 0.1.1, the number of changes introduced in 0.2 seemed too significant to be represented by only a minor increment. LSPDFR 0.2 goes some way in adressing much of the feedback after the first public release and is our first response, pun most definitely intended, to thousands of the comments we've received since then through the forums, YouTube and social media.
From the electroshocking glory of stun guns, to a blast from the past with the LCPDFR style search areas and pursuit blipping, LSPDFR 0.2 packs a serious punch and is a major improvement from our first offering.

Asking for ID in traffic stops - one of the many suggestions that have made their way into LSPDFR 0.2.
 
For those of you familiar with LCPDFR 1.1, the lack of search areas and blips in LSPDFR pursuits might have been confusing.  Fear no more, however, as we've reintroduced the system with much the same aesthetic style as that of before.  There are, however, some notable improvements including the way in which each unit in the pursuit is now being uniquely marked on the game's map.  This means that the legend at the side of the map can be used to highlight each different type of police vehicle currently involved.
We'll have more to share regarding the features in LSPDFR 0.2 tomorrow, when we'll move away from the pursuits and action sequences, and take a look at how 0.2 brings about better support of routine police work - something I know a lot of people are looking for.

i have the same issue. i've tried deleting everything in "startup.rhps" previously, didn't work for me either.
 
BUT here's how i worked my way around using the console at all; essentially you put all your plugins to writing in the startup.rhps file, include the "WarnOnPluginLoad false" line to play it safe.
WarnOnPluginLoad false
loadplugin "LSPD First Response.dll"
loadplugin "PlateChecker.dll"
loadplugin "speedradar.dll"
loadplugin "policeradio.dll"
 
mind you, this means lspdfr, platechecker, speedradar works from the get-go, but it doesn't change the fact that pressing f4 doesn't render the console visible. also the policeradio interface  isn't visible, but it works. pressing "c" brings up the interface, "Z" will then initiate a platecheck, "T" scrolls down aaaand so forth.