...
Enabling Purchase with Points Setting
Select Manage Settings from Members menu.
From Admin CP> Installed> select Activity point app
Scroll down to the settings for Purchasing Allow member to Purchase with Activity Points
- Activity Points Conversion Rate - Set the Conversion rate per currency. If you add currencies later, you need to remember to come back here and set it for any new ones added.
- Purchasing with Activity Points - Yes to allow users to purchase with points and No will disable this feature.
- Purchase Activity Points - This allows users to buy points from you. It requires you to have a payment gateway set up.
Enabling and Managing User Group Settings for Purchasing with Points
Each user group has its own settings for the Purchase with Points feature. You will need to check each user group and set it how you want it. Please see the User Group Settings tutorial for how to manage user groups.Once Once you are in select the user group you want to change, scroll down to the User settings, click that and to the right will be the see the list of settings . Find Can purchase with activity points? Click where you can manage and set permission for a specific user groups. Click Yes to enable or No to disable.
Note that there are default values for how many points are purchased. This is hardcoded and if you want to change that, you will need a developer to customize it.
Gift Points
You might want your users to be able to gift points to their friends as well. Once you enable them to be able to purchase with points, do the following:
When in the user group settings for this user group, select Core settings and to the right, find 
Allow to use Activity Points for exchanging items - Yes to allow users to purchase with points and No will disable this feature.
Allow member to Purchase Activity Points - This allows users to buy points from you. It requires you to have a payment gateway set up.
Can members of this user group gift activity points. Set to Yes for Enabled or No for disabled.
?- You might want your users to be able to gift points to their friends as well.
Setting Points for User Groups
Once you are in the user group manager and editing a user group, you You can set a number of points allowed per feature users will receive when doing things such as posting a blog, photo, etc. As an example, we will change the points for photo uploads.In the user group setting for your user group you are changing, select Photo settings and to the right, scroll down to the input box for Activity Points and change it how you want it. We changed ours to 10. That means for each photo From the Activity Point App setting page> click on Point Setting tab.
We set the number to 1. That means for each blog/attchment uploaded, the user will get 10 1 points. 
You can edit the number of your choice by clicking on the number.
Purchase Activity points
After enabling the setting Purchase Activity Points, users can purchase activity points following these below steps:
- Go to their user profile page.
- Click on the profile's drop-down menu, choose Activity Points.
- Click on Purchase Points link on Activity Points page.
- And specify the amount of point you want to buy Packages button on the right side of the page
- By clicking on the button it takes user to the Point Packages list where user can select package then make the purchase.
- After purchasing completely, Activity Points will be added to the account of the user.