[Urgent] Algorithm - detect BPM from a pulse sensor with a PICAXE18M2

Hi there to all freelancers. I have a project related with Pulse sensor available here : [login to view URL] . My problem is that I need to port the code written ( [login to view URL]) in Arduino IDE to Picaxe evironment OR do another basic algorithm. I have tried [take a look at [login to view URL] file] but I need help from you. I have some bugs. Sometimes I receive good values sometimes I don't. You will see for Arduino the code uses ISR for TMR to get an Interrupt. On my Picaxe I don't have availalble ISR for Timer so I didn't do the exact code. So, it's your choice - Fix my code for PICAXE18M2 - it's not so long, based on the actual algorithm already used for Arduino OR Create from the scratch an new algorithm with good results - [login to view URL] 300BPM,etc Keep in mind I need this thing to be done TODAY, but I will explain to you and help you. I have all things available here so you can use my computer to work - fast dev when you have physical things! Obviously, don't bid with high budget, just because I put this project with a maximum budget of 250used. Cheers, Gabriel