Sorry for the delayed response, I thought I had replied to this already, it looks like you perhaps removed the properties section of the pom file, that's where all of these items get their values from. Based on the error messages, it seems that's why these error messages are coming up. They should look something like this:
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<jar.finalName><your_snappack>-${VERSION}-${sl_build}</jar.finalName>
<snap><your_snappack></snap>
<package.build_no>${sl_build}</package.build_no>
<!-- This identifies the classes which represent the actual Snaps
(and become accessible on the Snaplex/JCC after deployment).
-->
<snap.classes>
...<all of the snap classes>
</snap.classes>
<!-- This identifies the classes which represent the actual Accounts
(and become accessible on the Snaplex/JCC after deployment).
-->
<account.classes>
...<all of the accounts>
</account.classes>
<!-- Enter your cc key prefix from keys.properties -->
<key.prefix>cc</key.prefix>
<!-- This is the user name that is authorized to deploy Snap Packs-->
<user>...<your username></user>
<!-- This is the organization name on the pod where the Snap Pack will be deployed. -->
<organization>...<your organization></organization>
<sl_build>0001</sl_build>
<VERSION>1</VERSION>
<!-- SnapLogic SDK versions -->
<snaplogic.platform.version>...<latest version></snaplogic.platform.version>
<snaplogic.snaps.version>...<latest version></snaplogic.snaps.version>
<!-- Maven plugin versions -->
<maven-assembly-plugin.version>3.2.0</maven-assembly-plugin.version>
<maven-compiler-plugin.version>3.5.1</maven-compiler-plugin.version>
<maven-dependency-plugin.version>3.1.2</maven-dependency-plugin.version>
<properties-maven-plugin.version>1.0.0</properties-maven-plugin.version>
<versions-maven-plugin.version>2.7</versions-maven-plugin.version>
</properties>
NOTE that you won't be able to simply copy these into your pom, if you removed items from it, you'll likely want to re-generate the package because that will have the appropriate correct values
