The unit provides the following link...

https://login.salesforce.com/packaging/installPackage.apexp?p0=04tj0000001mMYP

The component at that url is  the Opp Alert component which installs fine, however,  the challenge is looking for a ContactsToday component which is not installed.

How do I complete this unit?

I could use some assistance. We have a SalesForce customer portal and in a number of my orgs, the reset password email is not being sent to the users, either via the Forgot Password link or the Admin Reset Password button in User tab. The Forgot Username email works as expected though. The Forgot Password flow works fine in some of my other orgs and as far as I can tell, all settings are identical.

I have verified in Setup -> Email Administration -> Deliverability that Access Level is set to 'All email'.
In Setup -> Email Administration -> Test Deliverability, I have verified that I receive all 48 test emails.
In Setup -> Communication Templates -> Email Templates -> Forgot Password, I have tried the 'Send Test and Verify Merge Fields' and received the test email.
The Email Log File shows that all forgot password emails are being delivered and received (although they never actually make it to the inbox).

I am not sure if there is an issue with Site.forgotPassword() or if somehow the Forgot Password email template is not mapped properly to the Forgot Password workflow. I do know that the orgs that are having issues have the same managed package as the orgs that are working.  
Not sure where to go from here?

Any help is appreciated.

The validation rule should be on the Case object.
The validation rule should be named 'Mark_as_Escalated'.
The validation rule should fire if someone tries to set a case as escalated and it is closed, closed when created, or does not have a priority of High.
The validation rule should display the error message 'You can only set a case as escalated if it is high priority and not closed' under the Escalated field when triggered.
Add the 'Escalated' field to the Case page layout.

I am new to salesforce. I have a community for my users in sandbox.Community is in the preview mode.The login to the community site is working just fine, i can login to the community with the test user's credentials.The problem is when a user forgets their password and tries to reset it. It sends an email to the user with the template assigned to the Forgot Password community setting. The email template includes the {!Community_URL} merge field. Ideally the email received contains a link to the page with some type of reset token as a parameter(your_community_domain/communitiy_name/login?c=TOKEN),and it should be redirected to the change password page. But When the user clicks on the above link, it gets redirected to the link (your_community_domain/communitiy_name/secur/forgotpassword.jsp?r=some token) which redirects to login page and thus there is no way for them to reset their password. Interesting thing is as community is in preview mode ideally it should not be sending any forgot password mails, but in this case it is sending mail with wrong url.

So what should I do to fix this issue? Any kind of help will be appreciated.Thanks.